diff --git a/app/helpers/lightbox_helper.rb b/app/helpers/lightbox_helper.rb
index 1df9cab..5a23acd 100644
--- a/app/helpers/lightbox_helper.rb
+++ b/app/helpers/lightbox_helper.rb
@@ -25,4 +25,8 @@ module LightboxHelper
     options.merge(:class => the_class)
   end
 
+  def lightbox?
+    request.xhr?
+  end
+
 end
diff --git a/test/unit/lightbox_helper_text.rb b/test/unit/lightbox_helper_text.rb
index 10a7097..bf01891 100644
--- a/test/unit/lightbox_helper_text.rb
+++ b/test/unit/lightbox_helper_text.rb
@@ -44,4 +44,12 @@ class LightboxHelperTest < Test::Unit::TestCase
     assert_equal '[button]', lightbox_button('type', 'label', { :action => 'popup'})
   end
 
+  should 'tell if rendering inside lightbox' do
+    request = mock
+    expects(:request).returns(request)
+    request.espects(:xhr?).returns(true)
+
+    assert lightbox?
+  end
+
 end
--
libgit2 0.21.2