diff --git a/app/models/environment.rb b/app/models/environment.rb
index 915f8b5..237d89a 100644
--- a/app/models/environment.rb
+++ b/app/models/environment.rb
@@ -129,4 +129,9 @@ class Environment < ActiveRecord::Base
     self.find(:first, :conditions => [ 'is_default = ?', true ] )
   end
 
+  # returns an array with the top level categories for this environment. 
+  def top_level_categories
+    Category.top_level_for(self)
+  end
+
 end
diff --git a/test/unit/environment_test.rb b/test/unit/environment_test.rb
index 8e773a3..3ac9a1b 100644
--- a/test/unit/environment_test.rb
+++ b/test/unit/environment_test.rb
@@ -97,4 +97,16 @@ class EnvironmentTest < Test::Unit::TestCase
     assert_equal 'bli', v.flexible_template_icon_theme
   end
 
+  def test_should_list_top_level_categories
+    env = Environment.create!(:name => 'a test environment')
+    cat1 = Category.create!(:name => 'first category', :environment_id => env.id)
+    cat2 = Category.create!(:name => 'second category', :environment_id => env.id)
+
+    cats = env.top_level_categories
+    assert_equal 2, cats.size
+    assert cats.include?(cat1)
+    assert cats.include?(cat2)
+
+  end
+
 end
--
libgit2 0.21.2