diff --git a/app/controllers/organisations_controller.rb b/app/controllers/organisations_controller.rb
index dfe50fa22..9d3e63b33 100644
--- a/app/controllers/organisations_controller.rb
+++ b/app/controllers/organisations_controller.rb
@@ -4,8 +4,8 @@ class OrganisationsController < ApplicationController
   include DuplicateLogsHelper
 
   before_action :authenticate_user!
-  before_action :find_resource, except: %i[index new create]
-  before_action :authenticate_scope!, except: [:index]
+  before_action :find_resource, except: %i[index new create search]
+  before_action :authenticate_scope!, except: %i[index search]
   before_action :session_filters, if: -> { current_user.support? || current_user.organisation.has_managing_agents? }, only: %i[lettings_logs sales_logs email_lettings_csv download_lettings_csv email_sales_csv download_sales_csv]
   before_action :session_filters, only: %i[users schemes email_schemes_csv download_schemes_csv]
   before_action -> { filter_manager.serialize_filters_to_session }, if: -> { current_user.support? || current_user.organisation.has_managing_agents? }, only: %i[lettings_logs sales_logs email_lettings_csv download_lettings_csv email_sales_csv download_sales_csv]
@@ -280,6 +280,17 @@ class OrganisationsController < ApplicationController
     render "schemes/changes"
   end
 
+  def search
+    org_options = current_user.support? ? Organisation.all : Organisation.affiliated_organisations(current_user.organisation)
+    organisations = org_options.search_by(params["query"]).limit(20)
+
+    org_data = organisations.each_with_object({}) do |org, hash|
+      hash[org.id] = { value: org.name }
+    end
+
+    render json: org_data.to_json
+  end
+
 private
 
   def filter_type
diff --git a/app/controllers/users_controller.rb b/app/controllers/users_controller.rb
index 3fe3b1813..2f7bb2bd6 100644
--- a/app/controllers/users_controller.rb
+++ b/app/controllers/users_controller.rb
@@ -32,6 +32,17 @@ class UsersController < ApplicationController
     end
   end
 
+  def search
+    user_options = current_user.support? ? User.all : User.own_and_managing_org_users(current_user.organisation)
+    users = user_options.search_by(params["query"]).limit(20)
+
+    user_data = users.each_with_object({}) do |user, hash|
+      hash[user.id] = { value: user.name, hint: user.email }
+    end
+
+    render json: user_data.to_json
+  end
+
   def resend_invite
     @user.send_confirmation_instructions
     flash[:notice] = "Invitation sent to #{@user.email}"
diff --git a/app/frontend/controllers/index.js b/app/frontend/controllers/index.js
index ece539d15..ef29b99ca 100644
--- a/app/frontend/controllers/index.js
+++ b/app/frontend/controllers/index.js
@@ -13,6 +13,8 @@ import GovukfrontendController from './govukfrontend_controller.js'
 
 import NumericQuestionController from './numeric_question_controller.js'
 
+import SearchController from './search_controller.js'
+
 import FilterLayoutController from './filter_layout_controller.js'
 application.register('accessible-autocomplete', AccessibleAutocompleteController)
 application.register('conditional-filter', ConditionalFilterController)
@@ -20,3 +22,4 @@ application.register('conditional-question', ConditionalQuestionController)
 application.register('govukfrontend', GovukfrontendController)
 application.register('numeric-question', NumericQuestionController)
 application.register('filter-layout', FilterLayoutController)
+application.register('search', SearchController)
diff --git a/app/frontend/controllers/search_controller.js b/app/frontend/controllers/search_controller.js
new file mode 100644
index 000000000..565b9d0d1
--- /dev/null
+++ b/app/frontend/controllers/search_controller.js
@@ -0,0 +1,46 @@
+import { Controller } from '@hotwired/stimulus'
+import accessibleAutocomplete from 'accessible-autocomplete'
+import 'accessible-autocomplete/dist/accessible-autocomplete.min.css'
+import { searchSuggestion, fetchAndPopulateSearchResults, confirmSelectedOption, searchableName } from '../modules/search'
+
+const options = []
+const populateOptions = (results, selectEl) => {
+  selectEl.innerHTML = ''
+
+  Object.keys(results).forEach((key) => {
+    const option = document.createElement('option')
+    option.value = key
+    option.innerHTML = results[key].value
+    if (results[key].hint) { option.setAttribute('data-hint', results[key].hint) }
+    option.setAttribute('text', searchableName(results[key]))
+    selectEl.appendChild(option)
+    options.push(option)
+  })
+}
+
+export default class extends Controller {
+  connect () {
+    const selectEl = this.element
+    const matches = /^(\w+)\[(\w+)\]$/.exec(selectEl.name)
+    const rawFieldName = matches ? `${matches[1]}[${matches[2]}_raw]` : ''
+    const searchUrl = JSON.parse(this.element.dataset.info).search_url
+
+    document.querySelectorAll('.non-js-text-search-input-field').forEach((el) => {
+      el.style.display = 'none'
+    })
+
+    accessibleAutocomplete.enhanceSelectElement({
+      defaultValue: '',
+      selectElement: selectEl,
+      minLength: 1,
+      source: (query, populateResults) => {
+        fetchAndPopulateSearchResults(query, populateResults, searchUrl, populateOptions, selectEl)
+      },
+      autoselect: true,
+      placeholder: 'Start typing to search',
+      templates: { suggestion: (value) => searchSuggestion(value, options) },
+      name: rawFieldName,
+      onConfirm: (val) => confirmSelectedOption(selectEl, val)
+    })
+  }
+}
diff --git a/app/frontend/modules/search.js b/app/frontend/modules/search.js
index 71944746e..efdf7b9d0 100644
--- a/app/frontend/modules/search.js
+++ b/app/frontend/modules/search.js
@@ -117,6 +117,22 @@ export const suggestion = (value, options) => {
   }
 }
 
+export const searchSuggestion = (value, options) => {
+  try {
+    const option = options.find((o) => o.getAttribute('text') === value)
+    if (option) {
+      const result = enhanceOption(option)
+      const html = result.append ? `<span class="autocomplete__option__append">${result.text}</span> <span>${result.append}</span>` : `<span>${result.text}</span>`
+      return result.hint ? `${html}<div class="autocomplete__option__hint">${result.hint}</div>` : html
+    } else {
+      return '<span>No results found</span>'
+    }
+  } catch (error) {
+    console.error('Error fetching user option:', error)
+    return value
+  }
+}
+
 export const enhanceOption = (option) => {
   return {
     text: option.text,
@@ -128,6 +144,39 @@ export const enhanceOption = (option) => {
   }
 }
 
+export const fetchAndPopulateSearchResults = async (query, populateResults, relativeUrlRoute, populateOptions, selectEl) => {
+  if (/\S/.test(query)) {
+    const results = await fetchUserOptions(query, relativeUrlRoute)
+    populateOptions(results, selectEl)
+    populateResults(Object.values(results).map((o) => searchableName(o)))
+  }
+}
+
+export const fetchUserOptions = async (query, searchUrl) => {
+  try {
+    const response = await fetch(`${searchUrl}?query=${encodeURIComponent(query)}`)
+    const results = await response.json()
+    return results
+  } catch (error) {
+    console.error('Error fetching user options:', error)
+    return []
+  }
+}
+
 export const getSearchableName = (option) => {
   return option.getAttribute('data-hint') ? option.text + ' ' + option.getAttribute('data-hint') : option.text
 }
+
+export const searchableName = (option) => {
+  return option.hint ? option.value + ' ' + option.hint : option.value
+}
+
+export const confirmSelectedOption = (selectEl, val) => {
+  const arrayOfOptions = Array.from(selectEl.options).filter(function (option, index, arr) { return option.value !== '' })
+
+  const selectedOption = [].filter.call(
+    arrayOfOptions,
+    (option) => option.getAttribute('text') === val
+  )[0]
+  if (selectedOption) selectedOption.selected = true
+}
diff --git a/app/helpers/filters_helper.rb b/app/helpers/filters_helper.rb
index 38c15b82b..5f8488bc9 100644
--- a/app/helpers/filters_helper.rb
+++ b/app/helpers/filters_helper.rb
@@ -11,8 +11,8 @@ module FiltersHelper
     return true if !selected_filters.key?("owning_organisation") && filter == "owning_organisation_select" && value == :all
     return true if !selected_filters.key?("managing_organisation") && filter == "managing_organisation_select" && value == :all
 
-    return true if selected_filters["owning_organisation"].present? && filter == "owning_organisation_select" && value == :specific_org
-    return true if selected_filters["managing_organisation"].present? && filter == "managing_organisation_select" && value == :specific_org
+    return true if (selected_filters["owning_organisation"].present? || selected_filters["owning_organisation_text_search"].present?) && filter == "owning_organisation_select" && value == :specific_org
+    return true if (selected_filters["managing_organisation"].present? || selected_filters["managing_organisation_text_search"].present?) && filter == "managing_organisation_select" && value == :specific_org
 
     return false if selected_filters[filter].blank?
 
@@ -84,16 +84,54 @@ module FiltersHelper
     JSON.parse(session[session_name_for(filter_type)])[filter] || ""
   end
 
-  def owning_organisation_filter_options(user)
+  def all_owning_organisation_filter_options(user)
     organisation_options = user.support? ? Organisation.all : ([user.organisation] + user.organisation.stock_owners + user.organisation.absorbed_organisations).uniq
     [OpenStruct.new(id: "", name: "Select an option")] + organisation_options.map { |org| OpenStruct.new(id: org.id, name: org.name) }
   end
 
-  def assigned_to_filter_options(user)
+  def owning_organisation_filter_options(user, filter_type)
+    if applied_filters(filter_type)["owning_organisation"].present?
+      organisation_id = applied_filters(filter_type)["owning_organisation"]
+
+      org = if user.support?
+              Organisation.where(id: organisation_id)&.first
+            else
+              Organisation.affiliated_organisations(user.organisation).where(id: organisation_id)&.first
+            end
+      return [OpenStruct.new(id: org.id, name: org.name)] if org.present?
+    end
+
+    [OpenStruct.new(id: "", name: "Select an option")]
+  end
+
+  def assigned_to_csv_filter_options(user)
     user_options = user.support? ? User.all : (user.organisation.users + user.organisation.managing_agents.flat_map(&:users) + user.organisation.stock_owners.flat_map(&:users)).uniq
     [OpenStruct.new(id: "", name: "Select an option", hint: "")] + user_options.map { |user_option| OpenStruct.new(id: user_option.id, name: user_option.name, hint: user_option.email) }
   end
 
+  def assigned_to_filter_options(filter_type)
+    if applied_filters(filter_type)["assigned_to"] == "specific_user" && applied_filters(filter_type)["user"].present?
+      user_id = applied_filters(filter_type)["user"]
+      selected_user = if current_user.support?
+                        User.where(id: user_id)&.first
+                      else
+                        User.own_and_managing_org_users(current_user.organisation).where(id: user_id)&.first
+                      end
+
+      return [OpenStruct.new(id: selected_user.id, name: selected_user.name, hint: selected_user.email)] if selected_user.present?
+    end
+    [OpenStruct.new(id: "", name: "Select an option", hint: "")]
+  end
+
+  def filter_search_url(category)
+    case category
+    when :user
+      search_users_path
+    when :owning_organisation, :managing_organisation
+      search_organisations_path
+    end
+  end
+
   def collection_year_options
     years = {
       current_collection_start_year.to_s => year_combo(current_collection_start_year),
@@ -125,11 +163,26 @@ module FiltersHelper
     end
   end
 
-  def managing_organisation_filter_options(user)
+  def managing_organisation_csv_filter_options(user)
     organisation_options = user.support? ? Organisation.all : ([user.organisation] + user.organisation.managing_agents + user.organisation.absorbed_organisations).uniq
     [OpenStruct.new(id: "", name: "Select an option")] + organisation_options.map { |org| OpenStruct.new(id: org.id, name: org.name) }
   end
 
+  def managing_organisation_filter_options(user, filter_type)
+    if applied_filters(filter_type)["managing_organisation"].present?
+      organisation_id = applied_filters(filter_type)["managing_organisation"]
+
+      org = if user.support?
+              Organisation.where(id: organisation_id)&.first
+            else
+              Organisation.affiliated_organisations(user.organisation).where(id: organisation_id)&.first
+            end
+      return [OpenStruct.new(id: org.id, name: org.name)] if org.present?
+    end
+
+    [OpenStruct.new(id: "", name: "Select an option")]
+  end
+
   def show_scheme_managing_org_filter?(user)
     org = user.organisation
 
@@ -176,8 +229,8 @@ module FiltersHelper
       { id: "status", label: "Status", value: formatted_status_filter(session_filters) },
       filter_type == "lettings_logs" ? { id: "needstype", label: "Needs type", value: formatted_needstype_filter(session_filters) } : nil,
       { id: "assigned_to", label: "Assigned to", value: formatted_assigned_to_filter(session_filters) },
-      { id: "owned_by", label: "Owned by", value: formatted_owned_by_filter(session_filters) },
-      { id: "managed_by", label: "Managed by", value: formatted_managed_by_filter(session_filters) },
+      { id: "owned_by", label: "Owned by", value: formatted_owned_by_filter(session_filters, filter_type) },
+      { id: "managed_by", label: "Managed by", value: formatted_managed_by_filter(session_filters, filter_type) },
     ].compact
   end
 
@@ -221,7 +274,7 @@ private
     filters.each.sum do |category, category_filters|
       if %w[years status needstypes bulk_upload_id].include?(category)
         category_filters.count(&:present?)
-      elsif %w[user owning_organisation managing_organisation].include?(category)
+      elsif %w[user owning_organisation managing_organisation user_text_search owning_organisation_text_search managing_organisation_text_search].include?(category)
         1
       else
         0
@@ -256,26 +309,27 @@ private
     return "All" if session_filters["assigned_to"].include?("all")
     return "You" if session_filters["assigned_to"].include?("you")
 
-    selected_user_option = assigned_to_filter_options(current_user).find { |x| x.id == session_filters["user"].to_i }
+    User.own_and_managing_org_users(current_user.organisation).find(session_filters["user"].to_i).name
+    selected_user_option = User.own_and_managing_org_users(current_user.organisation).find(session_filters["user"].to_i)
     return unless selected_user_option
 
-    "#{selected_user_option.name} (#{selected_user_option.hint})"
+    "#{selected_user_option.name} (#{selected_user_option.email})"
   end
 
-  def formatted_owned_by_filter(session_filters)
+  def formatted_owned_by_filter(session_filters, filter_type)
     return "All" if params["id"].blank? && (session_filters["owning_organisation"].blank? || session_filters["owning_organisation"]&.include?("all"))
 
     session_org_id = session_filters["owning_organisation"] || params["id"]
-    selected_owning_organisation_option = owning_organisation_filter_options(current_user).find { |org| org.id == session_org_id.to_i }
+    selected_owning_organisation_option = owning_organisation_filter_options(current_user, filter_type).find { |org| org.id == session_org_id.to_i }
     return unless selected_owning_organisation_option
 
     selected_owning_organisation_option&.name
   end
 
-  def formatted_managed_by_filter(session_filters)
+  def formatted_managed_by_filter(session_filters, filter_type)
     return "All" if session_filters["managing_organisation"].blank? || session_filters["managing_organisation"].include?("all")
 
-    selected_managing_organisation_option = managing_organisation_filter_options(current_user).find { |org| org.id == session_filters["managing_organisation"].to_i }
+    selected_managing_organisation_option = managing_organisation_filter_options(current_user, filter_type).find { |org| org.id == session_filters["managing_organisation"].to_i }
     return unless selected_managing_organisation_option
 
     selected_managing_organisation_option&.name
diff --git a/app/models/lettings_log.rb b/app/models/lettings_log.rb
index e7a72350d..10ab612cd 100644
--- a/app/models/lettings_log.rb
+++ b/app/models/lettings_log.rb
@@ -132,6 +132,10 @@ class LettingsLog < Log
           illness_type_10: false)
   }
 
+  scope :filter_by_user_text_search, ->(param, user) { where(assigned_to: user.support? ? User.search_by(param) : User.own_and_managing_org_users(user.organisation).search_by(param)) }
+  scope :filter_by_owning_organisation_text_search, ->(param, _user) { where(owning_organisation: Organisation.search_by(param)) }
+  scope :filter_by_managing_organisation_text_search, ->(param, _user) { where(managing_organisation: Organisation.search_by(param)) }
+
   AUTOGENERATED_FIELDS = %w[id status created_at updated_at discarded_at].freeze
   OPTIONAL_FIELDS = %w[tenancycode propcode chcharge].freeze
   RENT_TYPE_MAPPING_LABELS = { 1 => "Social Rent", 2 => "Affordable Rent", 3 => "Intermediate Rent" }.freeze
diff --git a/app/models/log.rb b/app/models/log.rb
index c095a8276..3a6c1e982 100644
--- a/app/models/log.rb
+++ b/app/models/log.rb
@@ -53,6 +53,9 @@ class Log < ApplicationRecord
   scope :filter_by_organisation, ->(org, _user = nil) { where(owning_organisation: org).or(where(managing_organisation: org)) }
   scope :filter_by_owning_organisation, ->(owning_organisation, _user = nil) { where(owning_organisation:) }
   scope :filter_by_managing_organisation, ->(managing_organisation, _user = nil) { where(managing_organisation:) }
+  scope :filter_by_user_text_search, ->(param, user) { where(assigned_to: user.support? ? User.search_by(param) : User.own_and_managing_org_users(user.organisation).search_by(param)) }
+  scope :filter_by_owning_organisation_text_search, ->(param, _user) { where(owning_organisation: Organisation.search_by(param)) }
+  scope :filter_by_managing_organisation_text_search, ->(param, _user) { where(managing_organisation: Organisation.search_by(param)) }
 
   attr_accessor :skip_update_status, :skip_update_uprn_confirmed, :select_best_address_match, :skip_dpo_validation
 
diff --git a/app/models/organisation.rb b/app/models/organisation.rb
index 8f77df166..65b35c24e 100644
--- a/app/models/organisation.rb
+++ b/app/models/organisation.rb
@@ -18,6 +18,7 @@ class Organisation < ApplicationRecord
   belongs_to :absorbing_organisation, class_name: "Organisation", optional: true
   has_many :absorbed_organisations, class_name: "Organisation", foreign_key: "absorbing_organisation_id"
   scope :visible, -> { where(discarded_at: nil) }
+  scope :affiliated_organisations, ->(organisation) { where(id: (organisation.child_organisations + [organisation] + organisation.parent_organisations + organisation.absorbed_organisations).map(&:id)) }
 
   def affiliated_stock_owners
     ids = []
diff --git a/app/models/user.rb b/app/models/user.rb
index d25faaa53..c79ceb0d9 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -77,6 +77,7 @@ class User < ApplicationRecord
   scope :deactivated, -> { where(active: false) }
   scope :active_status, -> { where(active: true).where.not(last_sign_in_at: nil) }
   scope :visible, -> { where(discarded_at: nil) }
+  scope :own_and_managing_org_users, ->(organisation) { where(organisation: organisation.child_organisations + [organisation]) }
 
   def lettings_logs
     if support?
@@ -209,9 +210,9 @@ class User < ApplicationRecord
 
   def logs_filters(specific_org: false)
     if (support? && !specific_org) || organisation.has_managing_agents? || organisation.has_stock_owners?
-      %w[years status needstypes assigned_to user managing_organisation owning_organisation bulk_upload_id]
+      %w[years status needstypes assigned_to user managing_organisation owning_organisation bulk_upload_id user_text_search owning_organisation_text_search managing_organisation_text_search]
     else
-      %w[years status needstypes assigned_to user bulk_upload_id]
+      %w[years status needstypes assigned_to user bulk_upload_id user_text_search]
     end
   end
 
diff --git a/app/services/filter_manager.rb b/app/services/filter_manager.rb
index 8d661b3fa..9f68a097c 100644
--- a/app/services/filter_manager.rb
+++ b/app/services/filter_manager.rb
@@ -24,6 +24,9 @@ class FilterManager
       next if category == "owning_organisation" && all_orgs
       next if category == "managing_organisation" && all_orgs
       next if category == "assigned_to"
+      next if category == "user_text_search" && filters["assigned_to"] != "specific_user"
+      next if category == "owning_organisation_text_search" && all_orgs
+      next if category == "managing_organisation_text_search" && all_orgs
 
       logs = logs.public_send("filter_by_#{category}", values, user)
     end
@@ -94,11 +97,19 @@ class FilterManager
         new_filters[filter] = params[filter] if params[filter].present?
       end
 
+      if params["action"] == "download_csv"
+        new_filters["assigned_to"] = "all" if new_filters["assigned_to"] == "specific_user" && new_filters["user_text_search"].present?
+        new_filters["owning_organisation_select"] = "all" if new_filters["owning_organisation_select"] == "specific_organisation" && new_filters["owning_organisation_text_search"].present?
+        new_filters["managing_organisation_select"] = "all" if new_filters["managing_organisation_select"] == "specific_organisation" && new_filters["managing_organisation_text_search"].present?
+      end
       new_filters = new_filters.except("owning_organisation") if params["owning_organisation_select"] == "all"
       new_filters = new_filters.except("managing_organisation") if params["managing_organisation_select"] == "all"
 
       new_filters = new_filters.except("user") if params["assigned_to"] == "all"
       new_filters["user"] = current_user.id.to_s if params["assigned_to"] == "you"
+      new_filters = new_filters.except("user_text_search") if params["assigned_to"] == "all" || params["assigned_to"] == "you"
+      new_filters = new_filters.except("owning_organisation_text_search") if params["owning_organisation_select"] == "all"
+      new_filters = new_filters.except("managing_organisation_text_search") if params["managing_organisation_select"] == "all"
     end
 
     if (filter_type.include?("schemes") || filter_type.include?("users") || filter_type.include?("scheme_locations")) && params["status"].present?
diff --git a/app/views/filters/_radio_filter.html.erb b/app/views/filters/_radio_filter.html.erb
index 6eb902dba..e4d23573c 100644
--- a/app/views/filters/_radio_filter.html.erb
+++ b/app/views/filters/_radio_filter.html.erb
@@ -10,6 +10,7 @@
             collection: option[:conditional_filter][:options],
             category: option[:conditional_filter][:category],
             label: option[:conditional_filter][:label],
+            caption_text: option[:conditional_filter][:caption_text],
             secondary: true,
             hint_text: option[:conditional_filter][:hint_text],
           } %>
diff --git a/app/views/filters/_text_select_filter.html.erb b/app/views/filters/_text_select_filter.html.erb
new file mode 100644
index 000000000..ecc997bba
--- /dev/null
+++ b/app/views/filters/_text_select_filter.html.erb
@@ -0,0 +1,20 @@
+<span class="non-js-text-search-input-field">
+<%= f.govuk_text_field "#{category}_text_search".to_sym,
+  label: { text: label, hidden: secondary },
+  "data-controller": "search conditional-filter",
+  caption: { text: caption_text },
+  "data-info": { search_url: filter_search_url(category.to_sym) }.to_json,
+  value: selected_option("#{category}_text_search", @filter_type) %>
+</span>
+<%= f.govuk_select(category.to_sym,
+  label: { text: label, hidden: secondary },
+  "data-controller": "search conditional-filter",
+  "hidden": true,
+  "data-info": { search_url: filter_search_url(category.to_sym) }.to_json) do %>
+    <% collection.each do |answer| %>
+      <option value="<%= answer.id %>"
+        data-hint="<%= answer.hint %>"
+        <%= answer.id.to_s == selected_option(category, @filter_type).to_s ? "selected" : "" %>
+        <%= answer.id == "" ? "disabled" : "" %>><%= answer.name %></option>
+    <% end %>
+  <% end %>
diff --git a/app/views/filters/assigned_to.html.erb b/app/views/filters/assigned_to.html.erb
index 9f0582fbb..778d63c8a 100644
--- a/app/views/filters/assigned_to.html.erb
+++ b/app/views/filters/assigned_to.html.erb
@@ -11,7 +11,8 @@
                       type: "select",
                       label: "User",
                       category: "user",
-                      options: assigned_to_filter_options(current_user),
+                      caption_text: "User's name or email",
+                      options: assigned_to_csv_filter_options(current_user),
                     },
                   },
                 },
diff --git a/app/views/filters/managed_by.html.erb b/app/views/filters/managed_by.html.erb
index e3d849c9b..5d4b684f3 100644
--- a/app/views/filters/managed_by.html.erb
+++ b/app/views/filters/managed_by.html.erb
@@ -9,7 +9,8 @@
           type: "select",
           label: "Managed by",
           category: "managing_organisation",
-          options: managing_organisation_filter_options(current_user),
+          options: managing_organisation_csv_filter_options(current_user),
+          caption_text: "Organisation name",
         },
       },
     },
diff --git a/app/views/filters/owned_by.html.erb b/app/views/filters/owned_by.html.erb
index 7acfd459c..271b68de9 100644
--- a/app/views/filters/owned_by.html.erb
+++ b/app/views/filters/owned_by.html.erb
@@ -9,7 +9,8 @@
           type: "select",
           label: "Owning Organisation",
           category: "owning_organisation",
-          options: owning_organisation_filter_options(current_user),
+          options: all_owning_organisation_filter_options(current_user),
+          caption_text: "Organisation name",
         },
       },
     },
diff --git a/app/views/logs/_log_filters.html.erb b/app/views/logs/_log_filters.html.erb
index aaef70377..3beab4b6b 100644
--- a/app/views/logs/_log_filters.html.erb
+++ b/app/views/logs/_log_filters.html.erb
@@ -66,10 +66,11 @@
                        "specific_user": {
                          label: "Specific user",
                          conditional_filter: {
-                           type: "select",
+                           type: "text_select",
                            label: "User",
                            category: "user",
-                           options: assigned_to_filter_options(current_user),
+                           options: assigned_to_filter_options(@filter_type),
+                           caption_text: "User's name or email",
                          },
                        },
                      },
@@ -86,10 +87,11 @@
               "specific_org": {
                 label: "Specific owning organisation",
                 conditional_filter: {
-                  type: "select",
+                  type: "text_select",
                   label: "Owning Organisation",
                   category: "owning_organisation",
-                  options: owning_organisation_filter_options(current_user),
+                  options: owning_organisation_filter_options(current_user, @filter_type),
+                  caption_text: "Organisation name",
                 },
               },
             },
@@ -107,10 +109,11 @@
               "specific_org": {
                 label: "Specific managing organisation",
                 conditional_filter: {
-                  type: "select",
+                  type: "text_select",
                   label: user_or_org_lettings_path? ? "Managed by" : "Reported by",
                   category: "managing_organisation",
-                  options: managing_organisation_filter_options(current_user),
+                  options: managing_organisation_filter_options(current_user, @filter_type),
+                  caption_text: "Organisation name",
                 },
               },
             },
diff --git a/app/views/schemes/_scheme_filters.html.erb b/app/views/schemes/_scheme_filters.html.erb
index ca0538463..51687a096 100644
--- a/app/views/schemes/_scheme_filters.html.erb
+++ b/app/views/schemes/_scheme_filters.html.erb
@@ -35,7 +35,7 @@
                   type: "select",
                   label: "Owning Organisation",
                   category: "owning_organisation",
-                  options: owning_organisation_filter_options(current_user),
+                  options: all_owning_organisation_filter_options(current_user),
                 },
               },
             },
diff --git a/config/routes.rb b/config/routes.rb
index e0d9631e9..faea457fe 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -125,6 +125,10 @@ Rails.application.routes.draw do
     get "edit-dpo", to: "users#dpo"
     get "edit-key-contact", to: "users#key_contact"
 
+    collection do
+      get :search
+    end
+
     member do
       get "deactivate", to: "users#deactivate"
       get "reactivate", to: "users#reactivate"
@@ -191,6 +195,10 @@ Rails.application.routes.draw do
       get "delete-confirmation", to: "organisations#delete_confirmation"
       delete "delete", to: "organisations#delete"
     end
+
+    collection do
+      get :search
+    end
   end
 
   resources :merge_requests, path: "/merge-request" do
diff --git a/spec/features/lettings_log_spec.rb b/spec/features/lettings_log_spec.rb
index 2b977fdd7..ac9a1e4a8 100644
--- a/spec/features/lettings_log_spec.rb
+++ b/spec/features/lettings_log_spec.rb
@@ -89,9 +89,9 @@ RSpec.describe "Lettings Log Features" do
           check("In progress")
           choose("You")
           choose("Specific owning organisation")
-          select(stock_owner_1.name, from: "owning_organisation")
+          fill_in("owning-organisation-text-search-field", with: "stock")
           choose("Specific managing organisation")
-          select(managing_agent_1.name, from: "managing_organisation")
+          fill_in("managing-organisation-text-search-field", with: "managing")
           click_button("Apply filters")
         end
 
diff --git a/spec/features/organisation_spec.rb b/spec/features/organisation_spec.rb
index 65f787c2a..1867285eb 100644
--- a/spec/features/organisation_spec.rb
+++ b/spec/features/organisation_spec.rb
@@ -199,14 +199,14 @@ RSpec.describe "User Features" do
       it "can filter lettings logs by year" do
         check("years-2022-field")
         click_button("Apply filters")
-        expect(page).to have_current_path("/organisations/#{org_id}/lettings-logs?years[]=&years[]=2022&status[]=&needstypes[]=&assigned_to=all&user=&owning_organisation_select=all&owning_organisation=&managing_organisation_select=all&managing_organisation=")
+        expect(page).to have_current_path("/organisations/#{org_id}/lettings-logs?years[]=&years[]=2022&status[]=&needstypes[]=&assigned_to=all&user_text_search=&user=&owning_organisation_select=all&owning_organisation_text_search=&owning_organisation=&managing_organisation_select=all&managing_organisation_text_search=&managing_organisation=")
         expect(page).not_to have_link first_log.id.to_s, href: "/lettings-logs/#{first_log.id}"
       end
 
       it "can filter lettings logs by needstype" do
         check("needstypes-1-field")
         click_button("Apply filters")
-        expect(page).to have_current_path("/organisations/#{org_id}/lettings-logs?years[]=&status[]=&needstypes[]=&needstypes[]=1&assigned_to=all&user=&owning_organisation_select=all&owning_organisation=&managing_organisation_select=all&managing_organisation=")
+        expect(page).to have_current_path("/organisations/#{org_id}/lettings-logs?years[]=&status[]=&needstypes[]=&needstypes[]=1&assigned_to=all&user_text_search=&user=&owning_organisation_select=all&owning_organisation_text_search=&owning_organisation=&managing_organisation_select=all&managing_organisation_text_search=&managing_organisation=")
         other_general_needs_logs.each do |general_needs_log|
           expect(page).to have_link general_needs_log.id.to_s, href: "/lettings-logs/#{general_needs_log.id}"
         end
@@ -245,7 +245,7 @@ RSpec.describe "User Features" do
         end
         check("years-2022-field")
         click_button("Apply filters")
-        expect(page).to have_current_path("/organisations/#{org_id}/sales-logs?years[]=&years[]=2022&status[]=&assigned_to=all&user=&owning_organisation_select=all&owning_organisation=&managing_organisation_select=all&managing_organisation=")
+        expect(page).to have_current_path("/organisations/#{org_id}/sales-logs?years[]=&years[]=2022&status[]=&assigned_to=all&user_text_search=&user=&owning_organisation_select=all&owning_organisation_text_search=&owning_organisation=&managing_organisation_select=all&managing_organisation_text_search=&managing_organisation=")
         expect(page).not_to have_link first_log.id.to_s, href: "/sales-logs/#{first_log.id}"
       end
     end
diff --git a/spec/features/user_spec.rb b/spec/features/user_spec.rb
index 169465cb1..c30abe1e9 100644
--- a/spec/features/user_spec.rb
+++ b/spec/features/user_spec.rb
@@ -796,12 +796,13 @@ RSpec.describe "User Features" do
           visit("/lettings-logs")
           choose("owning-organisation-select-specific-org-field", allow_label_click: true)
           expect(page).to have_field("owning-organisation-field", with: "")
-          find("#owning-organisation-field").click.native.send_keys("F", "i", "l", "t", :down, :enter)
+          find("#owning-organisation-field").click.native.send_keys("F", "i", "l", "t")
+          select(parent_organisation.name, from: "owning-organisation-field-select", visible: false)
           click_button("Apply filters")
-          expect(page).to have_current_path("/lettings-logs?%5Byears%5D%5B%5D=&%5Bstatus%5D%5B%5D=&%5Bneedstypes%5D%5B%5D=&assigned_to=all&owning_organisation_select=specific_org&owning_organisation=#{parent_organisation.id}&managing_organisation_select=all")
+          expect(page).to have_current_path("/lettings-logs?%5Byears%5D%5B%5D=&%5Bstatus%5D%5B%5D=&%5Bneedstypes%5D%5B%5D=&assigned_to=all&user_text_search=&owning_organisation_select=specific_org&owning_organisation_text_search=&owning_organisation=#{parent_organisation.id}&managing_organisation_select=all&managing_organisation_text_search=")
           choose("owning-organisation-select-all-field", allow_label_click: true)
           click_button("Apply filters")
-          expect(page).to have_current_path("/lettings-logs?%5Byears%5D%5B%5D=&%5Bstatus%5D%5B%5D=&%5Bneedstypes%5D%5B%5D=&assigned_to=all&owning_organisation_select=all&managing_organisation_select=all")
+          expect(page).to have_current_path("/lettings-logs?%5Byears%5D%5B%5D=&%5Bstatus%5D%5B%5D=&%5Bneedstypes%5D%5B%5D=&assigned_to=all&user_text_search=&owning_organisation_select=all&owning_organisation_text_search=&managing_organisation_select=all&managing_organisation_text_search=")
         end
       end
     end
diff --git a/spec/helpers/filters_helper_spec.rb b/spec/helpers/filters_helper_spec.rb
index f04157521..c57f92311 100644
--- a/spec/helpers/filters_helper_spec.rb
+++ b/spec/helpers/filters_helper_spec.rb
@@ -175,27 +175,146 @@ RSpec.describe FiltersHelper do
     context "with a support user" do
       let(:user) { FactoryBot.create(:user, :support, organisation: child_organisation) }
 
-      it "returns a list of all organisations" do
-        expect(owning_organisation_filter_options(user)).to match_array([
-          OpenStruct.new(id: "", name: "Select an option"),
-          OpenStruct.new(id: child_organisation.id, name: "Child organisation"),
-          OpenStruct.new(id: absorbed_organisation.id, name: "Absorbed organisation"),
-          OpenStruct.new(id: parent_organisation.id, name: "Parent organisation"),
-          OpenStruct.new(id: 99, name: "Other organisation"),
-        ])
+      context "when no organisation is selected in the filters" do
+        it "returns an empty list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
+      end
+
+      context "when a specific child organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": child_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: child_organisation.id, name: "Child organisation"),
+          ])
+        end
+      end
+
+      context "when a specific parent organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": parent_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: parent_organisation.id, name: "Parent organisation"),
+          ])
+        end
+      end
+
+      context "when a specific absorbed organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": absorbed_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: absorbed_organisation.id, name: "Absorbed organisation"),
+          ])
+        end
+      end
+
+      context "when a specific non related organisation is selected in the filters" do
+        let(:unrelated_organisation) { create(:organisation, name: "Unrelated organisation") }
+
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": unrelated_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: unrelated_organisation.id, name: "Unrelated organisation"),
+          ])
+        end
+      end
+
+      context "when a non existing organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": 143_542_542 }.to_json
+        end
+
+        it "returns an empty list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
       end
     end
 
     context "with a data coordinator user" do
       let(:user) { FactoryBot.create(:user, :data_coordinator, organisation: child_organisation) }
 
-      it "returns a list of parent orgs and your own organisation" do
-        expect(owning_organisation_filter_options(user.reload)).to eq([
-          OpenStruct.new(id: "", name: "Select an option"),
-          OpenStruct.new(id: child_organisation.id, name: "Child organisation"),
-          OpenStruct.new(id: parent_organisation.id, name: "Parent organisation"),
-          OpenStruct.new(id: absorbed_organisation.id, name: "Absorbed organisation"),
-        ])
+      context "when no organisation is selected in the filters" do
+        it "returns an empty list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
+      end
+
+      context "when a specific child organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": child_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: child_organisation.id, name: "Child organisation"),
+          ])
+        end
+      end
+
+      context "when a specific parent organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": parent_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: parent_organisation.id, name: "Parent organisation"),
+          ])
+        end
+      end
+
+      context "when a specific absorbed organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": absorbed_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: absorbed_organisation.id, name: "Absorbed organisation"),
+          ])
+        end
+      end
+
+      context "when a specific non related organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": create(:organisation).id }.to_json
+        end
+
+        it "returns an empty list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
+      end
+
+      context "when a non existing organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "owning_organisation": 143_542_542 }.to_json
+        end
+
+        it "returns an empty list" do
+          expect(owning_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
       end
     end
   end
@@ -214,27 +333,146 @@ RSpec.describe FiltersHelper do
     context "with a support user" do
       let(:user) { FactoryBot.create(:user, :support, organisation: parent_organisation) }
 
-      it "returns a list of all organisations" do
-        expect(managing_organisation_filter_options(user)).to eq([
-          OpenStruct.new(id: "", name: "Select an option"),
-          OpenStruct.new(id: parent_organisation.id, name: "Parent organisation"),
-          OpenStruct.new(id: absorbed_organisation.id, name: "Absorbed organisation"),
-          OpenStruct.new(id: child_organisation.id, name: "Child organisation"),
-          OpenStruct.new(id: 99, name: "Other organisation"),
-        ])
+      context "when no organisation is selected in the filters" do
+        it "returns an empty list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
+      end
+
+      context "when a specific child organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": child_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: child_organisation.id, name: "Child organisation"),
+          ])
+        end
+      end
+
+      context "when a specific parent organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": parent_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: parent_organisation.id, name: "Parent organisation"),
+          ])
+        end
+      end
+
+      context "when a specific absorbed organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": absorbed_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: absorbed_organisation.id, name: "Absorbed organisation"),
+          ])
+        end
+      end
+
+      context "when a specific non related organisation is selected in the filters" do
+        let(:unrelated_organisation) { create(:organisation, name: "Unrelated organisation") }
+
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": unrelated_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: unrelated_organisation.id, name: "Unrelated organisation"),
+          ])
+        end
+      end
+
+      context "when a non existing organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": 143_542_542 }.to_json
+        end
+
+        it "returns an empty list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
       end
     end
 
     context "with a data coordinator user" do
       let(:user) { FactoryBot.create(:user, :data_coordinator, organisation: parent_organisation) }
 
-      it "returns a list of child orgs and your own organisation" do
-        expect(managing_organisation_filter_options(user.reload)).to eq([
-          OpenStruct.new(id: "", name: "Select an option"),
-          OpenStruct.new(id: parent_organisation.id, name: "Parent organisation"),
-          OpenStruct.new(id: child_organisation.id, name: "Child organisation"),
-          OpenStruct.new(id: absorbed_organisation.id, name: "Absorbed organisation"),
-        ])
+      context "when no organisation is selected in the filters" do
+        it "returns an empty list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
+      end
+
+      context "when a specific child organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": child_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: child_organisation.id, name: "Child organisation"),
+          ])
+        end
+      end
+
+      context "when a specific parent organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": parent_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: parent_organisation.id, name: "Parent organisation"),
+          ])
+        end
+      end
+
+      context "when a specific absorbed organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": absorbed_organisation.id }.to_json
+        end
+
+        it "returns the selected organisation in the list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: absorbed_organisation.id, name: "Absorbed organisation"),
+          ])
+        end
+      end
+
+      context "when a specific non related organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": create(:organisation).id }.to_json
+        end
+
+        it "returns an empty list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
+      end
+
+      context "when a non existing organisation is selected in the filters" do
+        before do
+          session[:lettings_logs_filters] = { "managing_organisation": 143_542_542 }.to_json
+        end
+
+        it "returns an empty list" do
+          expect(managing_organisation_filter_options(user.reload, "lettings_logs")).to eq([
+            OpenStruct.new(id: "", name: "Select an option"),
+          ])
+        end
       end
     end
   end
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
index edb998ac3..6a04e9a0b 100644
--- a/spec/models/user_spec.rb
+++ b/spec/models/user_spec.rb
@@ -164,7 +164,7 @@ RSpec.describe User, type: :model do
         end
 
         it "can filter lettings logs by user, year and status" do
-          expect(user.logs_filters).to match_array(%w[years status needstypes assigned_to user bulk_upload_id])
+          expect(user.logs_filters).to match_array(%w[years status needstypes assigned_to user bulk_upload_id user_text_search])
         end
       end
 
@@ -174,7 +174,7 @@ RSpec.describe User, type: :model do
         end
 
         it "can filter lettings logs by user, year, status, managing_organisation and owning_organisation" do
-          expect(user.logs_filters).to match_array(%w[years status needstypes assigned_to user managing_organisation owning_organisation bulk_upload_id])
+          expect(user.logs_filters).to match_array(%w[years status needstypes assigned_to user managing_organisation owning_organisation bulk_upload_id managing_organisation_text_search owning_organisation_text_search user_text_search])
         end
       end
     end
@@ -215,7 +215,7 @@ RSpec.describe User, type: :model do
       end
 
       it "can filter lettings logs by user, year, status, managing_organisation and owning_organisation" do
-        expect(user.logs_filters).to match_array(%w[years status needstypes assigned_to user owning_organisation managing_organisation bulk_upload_id])
+        expect(user.logs_filters).to match_array(%w[years status needstypes assigned_to user owning_organisation managing_organisation bulk_upload_id managing_organisation_text_search owning_organisation_text_search user_text_search])
       end
     end
 
diff --git a/spec/requests/organisations_controller_spec.rb b/spec/requests/organisations_controller_spec.rb
index 13879a38c..d3e8a8155 100644
--- a/spec/requests/organisations_controller_spec.rb
+++ b/spec/requests/organisations_controller_spec.rb
@@ -75,6 +75,13 @@ RSpec.describe OrganisationsController, type: :request do
         end
       end
     end
+
+    describe "#search" do
+      it "redirects to the sign in page" do
+        get "/organisations/search"
+        expect(response).to redirect_to("/account/sign-in")
+      end
+    end
   end
 
   context "when user is signed in" do
@@ -807,6 +814,25 @@ RSpec.describe OrganisationsController, type: :request do
           end
         end
       end
+
+      describe "#search" do
+        let(:parent_organisation) { create(:organisation, name: "parent test organisation") }
+        let(:child_organisation) { create(:organisation, name: "child test organisation") }
+
+        before do
+          user.organisation.update!(name: "test organisation")
+          create(:organisation_relationship, parent_organisation: user.organisation, child_organisation:)
+          create(:organisation_relationship, child_organisation: user.organisation, parent_organisation:)
+          create(:organisation, name: "other organisation test organisation")
+        end
+
+        it "only searches within the current user's organisation, managing agents and stock owners" do
+          get "/organisations/search", headers:, params: { query: "test organisation" }
+          result = JSON.parse(response.body)
+          expect(result.count).to eq(3)
+          expect(result.keys).to match_array([user.organisation.id.to_s, parent_organisation.id.to_s, child_organisation.id.to_s])
+        end
+      end
     end
 
     context "with a data provider user" do
@@ -2077,6 +2103,25 @@ RSpec.describe OrganisationsController, type: :request do
           end
         end
       end
+
+      describe "#search" do
+        let(:parent_organisation) { create(:organisation, name: "parent test organisation") }
+        let(:child_organisation) { create(:organisation, name: "child test organisation") }
+        let!(:other_organisation) { create(:organisation, name: "other organisation test organisation") }
+
+        before do
+          user.organisation.update!(name: "test organisation")
+          create(:organisation_relationship, parent_organisation: user.organisation, child_organisation:)
+          create(:organisation_relationship, child_organisation: user.organisation, parent_organisation:)
+        end
+
+        it "searches within all the organisations" do
+          get "/organisations/search", headers:, params: { query: "test organisation" }
+          result = JSON.parse(response.body)
+          expect(result.count).to eq(4)
+          expect(result.keys).to match_array([user.organisation.id.to_s, parent_organisation.id.to_s, child_organisation.id.to_s, other_organisation.id.to_s])
+        end
+      end
     end
   end
 
diff --git a/spec/requests/users_controller_spec.rb b/spec/requests/users_controller_spec.rb
index bb0a1cca3..8e87f7f28 100644
--- a/spec/requests/users_controller_spec.rb
+++ b/spec/requests/users_controller_spec.rb
@@ -117,6 +117,13 @@ RSpec.describe UsersController, type: :request do
         expect(response).to redirect_to("/account/sign-in")
       end
     end
+
+    describe "#search" do
+      it "redirects to the sign in page" do
+        get "/users/search"
+        expect(response).to redirect_to("/account/sign-in")
+      end
+    end
   end
 
   context "when user is signed in as a data provider" do
@@ -404,6 +411,25 @@ RSpec.describe UsersController, type: :request do
         expect(response).to have_http_status(:unauthorized)
       end
     end
+
+    describe "#search" do
+      let(:parent_relationship) { create(:organisation_relationship, parent_organisation: user.organisation) }
+      let(:child_relationship) { create(:organisation_relationship, child_organisation: user.organisation) }
+      let!(:org_user) { create(:user, organisation: user.organisation, name: "test_name") }
+      let!(:managing_user) { create(:user, organisation: parent_relationship.child_organisation, name: "managing_agent_test_name") }
+
+      before do
+        create(:user, organisation: child_relationship.parent_organisation, name: "stock_owner_test_name")
+        create(:user, name: "other_organisation_test_name")
+      end
+
+      it "only searches within the current user's organisation and managing agents" do
+        get "/users/search", headers:, params: { query: "test_name" }
+        result = JSON.parse(response.body)
+        expect(result.count).to eq(2)
+        expect(result.keys).to match_array([org_user.id.to_s, managing_user.id.to_s])
+      end
+    end
   end
 
   context "when user is signed in as a data coordinator" do
@@ -1174,6 +1200,25 @@ RSpec.describe UsersController, type: :request do
         expect(response).to have_http_status(:unauthorized)
       end
     end
+
+    describe "#search" do
+      let(:parent_relationship) { create(:organisation_relationship, parent_organisation: user.organisation) }
+      let(:child_relationship) { create(:organisation_relationship, child_organisation: user.organisation) }
+      let!(:org_user) { create(:user, organisation: user.organisation, email: "test_name@example.com") }
+      let!(:managing_user) { create(:user, organisation: parent_relationship.child_organisation, email: "managing_agent_test_name@example.com") }
+
+      before do
+        create(:user, email: "other_organisation_test_name@example.com")
+        create(:user, organisation: child_relationship.parent_organisation, email: "stock_owner_test_name@example.com")
+      end
+
+      it "only searches within the current user's organisation and managing agents" do
+        get "/users/search", headers:, params: { query: "test_name" }
+        result = JSON.parse(response.body)
+        expect(result.count).to eq(2)
+        expect(result.keys).to match_array([org_user.id.to_s, managing_user.id.to_s])
+      end
+    end
   end
 
   context "when user is signed in as a support user" do
@@ -2111,6 +2156,22 @@ RSpec.describe UsersController, type: :request do
         expect(page).not_to have_link("User to be deleted")
       end
     end
+
+    describe "#search" do
+      let(:parent_relationship) { create(:organisation_relationship, parent_organisation: user.organisation) }
+      let(:child_relationship) { create(:organisation_relationship, child_organisation: user.organisation) }
+      let!(:org_user) { create(:user, organisation: user.organisation, name: "test_name") }
+      let!(:managing_user) { create(:user, organisation: child_relationship.parent_organisation, name: "stock_owner_test_name") }
+      let!(:owner_user) { create(:user, organisation: parent_relationship.child_organisation, name: "managing_agent_test_name") }
+      let!(:other_user) { create(:user, name: "other_organisation_test_name") }
+
+      it "searches all users" do
+        get "/users/search", headers:, params: { query: "test_name" }
+        result = JSON.parse(response.body)
+        expect(result.count).to eq(4)
+        expect(result.keys).to match_array([org_user.id.to_s, managing_user.id.to_s, owner_user.id.to_s, other_user.id.to_s])
+      end
+    end
   end
 
   describe "title link" do