diff --git a/features/process_with_sprockets.feature b/features/process_with_sprockets.feature
index 3ae262a..6173abd 100644
--- a/features/process_with_sprockets.feature
+++ b/features/process_with_sprockets.feature
@@ -1,5 +1,5 @@
 Feature: Process files with Sprockets
-  Scenario: Simple Sprockets work
+  Background:
     Given I have the file "dir/file.js" with the content:
       """
       //= require other
@@ -9,6 +9,8 @@ Feature: Process files with Sprockets
       """
       another file
       """
+
+  Scenario: Simple Sprockets work
     When I instantiate a Sprockets handler with the following asset directories:
       | dir |
       And I work with the Sprockets asset "file"
@@ -16,3 +18,18 @@ Feature: Process files with Sprockets
       | dir/other.js |
       | dir/file.js |
 
+  Scenario: Require the file twice
+    Given I have the file "dir/third.js" with the content:
+      """
+      //= require other
+      third file
+      """
+    When I instantiate a Sprockets handler with the following asset directories:
+      | dir |
+      And I work with the Sprockets asset "file"
+      And I work with the Sprockets asset "third"
+    Then the handler should have the following files in order:
+      | dir/other.js |
+      | dir/file.js |
+      | dir/third.js |
+
diff --git a/lib/flowerbox/delivery.rb b/lib/flowerbox/delivery.rb
index 2174765..4ece455 100644
--- a/lib/flowerbox/delivery.rb
+++ b/lib/flowerbox/delivery.rb
@@ -3,6 +3,7 @@ module Flowerbox
     autoload :Server, 'flowerbox/delivery/server'
     autoload :TemplateRenderer, 'flowerbox/delivery/template_renderer'
     autoload :SprocketsHandler, 'flowerbox/delivery/sprockets_handler'
+    autoload :UniqueAssetList, 'flowerbox/delivery/unique_asset_list'
   end
 end
 
diff --git a/lib/flowerbox/delivery/sprockets_handler.rb b/lib/flowerbox/delivery/sprockets_handler.rb
index a4e29c6..d6386a5 100644
--- a/lib/flowerbox/delivery/sprockets_handler.rb
+++ b/lib/flowerbox/delivery/sprockets_handler.rb
@@ -7,11 +7,11 @@ module Flowerbox::Delivery
     def initialize(options)
       @options = options
 
-      @files = []
+      @files = UniqueAssetList.new
     end
 
     def add(asset)
-      @files += paths_for(asset)
+      @files.add(paths_for(asset))
     end
 
     def paths_for(asset)
diff --git a/lib/flowerbox/delivery/unique_asset_list.rb b/lib/flowerbox/delivery/unique_asset_list.rb
new file mode 100644
index 0000000..cfb58e3
--- /dev/null
+++ b/lib/flowerbox/delivery/unique_asset_list.rb
@@ -0,0 +1,13 @@
+module Flowerbox::Delivery
+  class UniqueAssetList < ::Array
+    def add(files)
+      files.each { |file| self << file if !include?(file) }
+    end
+
+    private
+    def include?(file)
+      any? { |other_file| other_file == file }
+    end
+  end
+end
+
diff --git a/spec/flowerbox/delivery/unique_asset_list_spec.rb b/spec/flowerbox/delivery/unique_asset_list_spec.rb
new file mode 100644
index 0000000..33fbae5
--- /dev/null
+++ b/spec/flowerbox/delivery/unique_asset_list_spec.rb
@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+describe Flowerbox::Delivery::UniqueAssetList do
+  let(:unique_asset_list) { described_class.new }
+
+  describe "#add" do
+    let(:first) { Pathname.new('one') }
+    let(:second) { Pathname.new('one') }
+    let(:third) { Pathname.new('two') }
+
+    it 'should not add assets already added' do
+      unique_asset_list.add([ first, second, third ])
+
+      unique_asset_list.should == [ first, third ]
+    end
+  end
+end