diff --git a/app/helpers/observation_units_helper.rb b/app/helpers/observation_units_helper.rb
new file mode 100644
index 0000000000..4c1a854ba8
--- /dev/null
+++ b/app/helpers/observation_units_helper.rb
@@ -0,0 +1,24 @@
+module ObservationUnitsHelper
+
+  def observation_unit_selector(name, selected = nil, opts = {})
+    opts[:data] ||= {}
+    opts[:multiple] = false
+    grouped_options = grouped_observation_unit_options
+    opts[:select_options] = grouped_options_for_select(grouped_options, selected)
+
+    objects_input(name, [selected&.id], opts)
+  end
+
+  private
+
+  def grouped_observation_unit_options
+    obs_units = authorised_assets(ObservationUnit, nil, :edit)
+    grouped = obs_units.group_by(&:study)
+    grouped.keys.collect do |study|
+      title = study&.can_view? ? study.title : "Hidden #{t('study')}"
+      [title, grouped[study].collect{|obs_unit| [obs_unit.title, obs_unit.id]}]
+    end
+
+  end
+
+end
\ No newline at end of file
diff --git a/app/views/samples/_associate_observation_unit.html.erb b/app/views/samples/_associate_observation_unit.html.erb
new file mode 100644
index 0000000000..87d05fe363
--- /dev/null
+++ b/app/views/samples/_associate_observation_unit.html.erb
@@ -0,0 +1,3 @@
+<%= folding_panel(t('observation_unit'), resource.observation_unit.present?) do %>
+  <%= observation_unit_selector('sample[observation_unit_id]', resource.observation_unit) %>
+<% end %>
\ No newline at end of file
diff --git a/app/views/samples/_form.html.erb b/app/views/samples/_form.html.erb
index 2e4932113f..d092fd73fb 100644
--- a/app/views/samples/_form.html.erb
+++ b/app/views/samples/_form.html.erb
@@ -24,5 +24,7 @@
     <% end %>
   </div>
 
+  <%= render partial: 'associate_observation_unit', locals: {f: f, resource: @sample} if Seek::Config.observation_units_enabled %>
+
   <%= form_submit_buttons(@sample, validate:false) %>
 </div>
\ No newline at end of file
diff --git a/test/functional/samples_controller_test.rb b/test/functional/samples_controller_test.rb
index 871e9b675d..23d5293b90 100644
--- a/test/functional/samples_controller_test.rb
+++ b/test/functional/samples_controller_test.rb
@@ -227,7 +227,9 @@ def rdf_test_object
   end
 
   test 'edit' do
-    login_as(FactoryBot.create(:person))
+    person = FactoryBot.create(:person)
+    login_as(person)
+    FactoryBot.create(:observation_unit, contributor: person)
 
     get :edit, params: { id: populated_patient_sample.id }