diff --git a/app/controllers/services_controller.rb b/app/controllers/services_controller.rb
index 376efc52..5e6823a2 100644
--- a/app/controllers/services_controller.rb
+++ b/app/controllers/services_controller.rb
@@ -9,11 +9,16 @@ class ServicesController < ApplicationController
 
   def create
     service = Service.initialize_from_omniauth( omniauth_hash )
+    service.user = current_user
 
-    if current_user.services << service
+    if service.save
       flash[:success] = t('flash.service.create.success')
     else
-      flash[:error] = t('flash.service.create.error')
+      if service.errors.details.has_key?(:uid) && service.errors.details[:uid].any? { |err| err[:error] == :taken }
+        flash[:error] = "The #{service.type.split('::').last.titleize} account you are trying to connect is already connected to another #{APP_CONFIG['site_name']} account. If you are unable to disconnect the account yourself, please send us a Direct Message on Twitter: @retrospring."
+      else
+        flash[:error] = t('flash.service.create.error')
+      end
     end
 
     if origin
diff --git a/spec/controllers/services_controller_spec.rb b/spec/controllers/services_controller_spec.rb
new file mode 100644
index 00000000..112e97e1
--- /dev/null
+++ b/spec/controllers/services_controller_spec.rb
@@ -0,0 +1,41 @@
+require 'rails_helper'
+
+describe ServicesController, type: :controller do
+  context 'successful Twitter sign in' do
+    let(:user) { FactoryBot.create(:user) }
+
+    before do
+      sign_in user
+      OmniAuth.config.test_mode = true
+      OmniAuth.config.mock_auth[:twitter] = OmniAuth::AuthHash.new({
+                                                                     'provider' => 'twitter',
+                                                                     'uid' => '12',
+                                                                     'info' => { 'nickname' => 'jack' },
+                                                                     'credentials' => { 'token' => 'AAAA', 'secret' => 'BBBB' }
+                                                                   })
+      request.env["omniauth.auth"] = OmniAuth.config.mock_auth[:twitter]
+    end
+
+    after do
+      OmniAuth.config.mock_auth[:twitter] = nil
+    end
+
+    subject { get :create, params: { provider: 'twitter' } }
+
+    context 'no services connected' do
+      it 'creates a service integration' do
+        expect { subject }.to change { Service.count }.by(1)
+      end
+    end
+
+    context 'a user has a service connected' do
+      let(:other_user) { FactoryBot.create(:user) }
+      let!(:service) { Services::Twitter.create(user: other_user, uid: 12) }
+
+      it 'shows an error when trying to attach a service account which is already connected' do
+        subject
+        expect(flash[:error]).to eq("The Twitter account you are trying to connect is already connected to another #{APP_CONFIG['site_name']} account. If you are unable to disconnect the account yourself, please send us a Direct Message on Twitter: @retrospring.")
+      end
+    end
+  end
+end