diff --git a/app/components/admin/custom_fields/hierarchy/change_item_parent_dialog_component.html.erb b/app/components/admin/custom_fields/hierarchy/change_item_parent_dialog_component.html.erb
index c03a235ccc8..dc43525e528 100644
--- a/app/components/admin/custom_fields/hierarchy/change_item_parent_dialog_component.html.erb
+++ b/app/components/admin/custom_fields/hierarchy/change_item_parent_dialog_component.html.erb
@@ -28,18 +28,25 @@ See COPYRIGHT and LICENSE files for more details.
 ++#%>
 
 <%=
-  render Primer::Alpha::Dialog.new(id: dialog_id, title: I18n.t(:label_change_parent)) do |dialog|
+  render(
+    Primer::Alpha::Dialog.new(
+      id: dialog_id,
+      title: I18n.t(:label_change_parent),
+      size: :medium_portrait
+    )
+  ) do |dialog|
     dialog.with_body do
-      primer_form_with(**form_arguments) do |f|
-        helpers.render_inline_form(f) do |form|
-          form.text_field(name: :new_parent, label: "New Parent")
+      primer_form_with(**form_arguments) do |form|
+        render(
+          Primer::OpenProject::FilterableTreeView.new(form_arguments: { builder: form, name: :new_parent })
+        ) do |tree_view|
+          add_sub_tree(tree_view, hierarchy_items)
         end
       end
     end
 
     dialog.with_footer(show_divider: true) do
       concat(render(Primer::Beta::Button.new(data: { close_dialog_id: dialog_id })) { I18n.t(:button_cancel) })
-
       concat(
         render(
           Primer::Beta::Button.new(
diff --git a/app/components/admin/custom_fields/hierarchy/change_item_parent_dialog_component.rb b/app/components/admin/custom_fields/hierarchy/change_item_parent_dialog_component.rb
index d75daaa5b96..d424ee57919 100644
--- a/app/components/admin/custom_fields/hierarchy/change_item_parent_dialog_component.rb
+++ b/app/components/admin/custom_fields/hierarchy/change_item_parent_dialog_component.rb
@@ -48,17 +48,50 @@ module Admin
 
         def form_arguments
           {
-            form_id:,
+            id: form_id,
             url: change_parent_custom_field_item_path(custom_field_id: @custom_field.id, id: @hierarchy_item.id),
             model: form_model,
             method: :post
           }
         end
 
+        def hierarchy_items
+          hashed_hierarchy = @custom_field.hierarchy_root.hash_tree
+          hashed_hierarchy.keys.first.label = @custom_field.name
+
+          hashed_hierarchy
+        end
+
+        def add_sub_tree(tree, hierarchy_hash)
+          hierarchy_hash.each do |item, child_hash|
+            if child_hash.empty?
+              tree.with_leaf(**item_options(item))
+            else
+              expanded = current?(item) || child_hash.any? { |child, _| current?(child) }
+
+              tree.with_sub_tree(expanded:, **item_options(item)) do |sub_tree|
+                add_sub_tree(sub_tree, child_hash)
+              end
+            end
+          end
+        end
+
         private
 
         def form_model
-          CustomField::Hierarchy::Forms::NewParentFormModel.new(new_parent: nil)
+          CustomField::Hierarchy::Forms::NewParentFormModel.new(new_parent: [])
+        end
+
+        def item_options(item)
+          {
+            label: item.label,
+            current: current?(item),
+            value: item.id
+          }
+        end
+
+        def current?(item)
+          item.id == @hierarchy_item.id
         end
       end
     end
diff --git a/app/controllers/admin/custom_fields/hierarchy/items_controller.rb b/app/controllers/admin/custom_fields/hierarchy/items_controller.rb
index b5fd7ba86b5..03de873e437 100644
--- a/app/controllers/admin/custom_fields/hierarchy/items_controller.rb
+++ b/app/controllers/admin/custom_fields/hierarchy/items_controller.rb
@@ -33,6 +33,7 @@ module Admin
     module Hierarchy
       class ItemsController < ApplicationController
         include OpTurbo::ComponentStream
+        include Dry::Monads[:result]
 
         layout :admin_or_frame_layout
         model_object CustomField
@@ -103,11 +104,25 @@ module Admin
         end
 
         def change_parent
-          permitted = params.expect(custom_field_hierarchy_forms_new_parent_form_model: [:new_parent])
-          new_parent = CustomField::Hierarchy::Item.including_children.find(permitted[:new_parent])
-          item_service.move_item(item: @active_item, new_parent:)
+          result = parse_parent_input(new_parent_params).bind do |new_parent|
+            validate_new_parent(new_parent).bind do
+              item_service.move_item(item: @active_item, new_parent:)
+            end
+          end
 
-          redirect_to(custom_field_item_path(@custom_field, new_parent), status: :see_other)
+          result.either(
+            ->(result) do
+              redirect_to(
+                custom_field_item_path(@custom_field, result.parent),
+                status: :see_other,
+                notice: I18n.t(:notice_successful_update)
+              )
+            end,
+            ->(error) do
+              render_error_flash_message_via_turbo_stream(message: error)
+              respond_with_turbo_streams(&:html)
+            end
+          )
         end
 
         def destroy
@@ -147,6 +162,10 @@ module Admin
           input
         end
 
+        def new_parent_params
+          params.require(:custom_field_hierarchy_forms_new_parent_form_model).require(:new_parent)
+        end
+
         def create_contract
           case @custom_field.field_format
           when "hierarchy"
@@ -184,6 +203,29 @@ module Admin
           end
         end
 
+        def parse_parent_input(new_parent_input)
+          case new_parent_input
+          in [new_parent]
+            input = MultiJson.load(new_parent, symbolize_keys: true)[:value]
+            new_parent = CustomField::Hierarchy::Item.including_children.find_by(id: input)
+
+            if new_parent.present?
+              Success(new_parent)
+            else
+              Failure("Cannot find parent with id: #{input}")
+            end
+          else
+            Failure("Invalid input: #{new_parent_input}")
+          end
+        end
+
+        def validate_new_parent(new_parent)
+          return Failure("Parent must not be the same as before.") if @active_item.parent.id == new_parent.id
+          return Failure("Parent must not be the current item.") if @active_item.id == new_parent.id
+
+          Success()
+        end
+
         def find_model_object
           @object = CustomField.hierarchy_root_and_children.find(params[:custom_field_id])
           @custom_field = @object