diff --git a/.gitignore b/.gitignore
index 9fc6054..6feda87 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,5 +3,6 @@
 Gemfile.lock
 gemfiles/Gemfile-rails.3.0.x.lock
 gemfiles/Gemfile-rails.3.1.x.lock
+gemfiles/Gemfile-sinatra.lock
 pkg/*
 log
diff --git a/.travis.yml b/.travis.yml
index 30ca637..0bc8f38 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,7 @@ rvm:
   - 2.0.0
   - ruby-head
 gemfile:
+  - gemfiles/Gemfile-sinatra
   - gemfiles/Gemfile-rails.3.0.x
   - gemfiles/Gemfile-rails.3.1.x
   - Gemfile
diff --git a/active_decorator.gemspec b/active_decorator.gemspec
index 4d4e253..bf2ae2a 100644
--- a/active_decorator.gemspec
+++ b/active_decorator.gemspec
@@ -17,4 +17,6 @@ Gem::Specification.new do |s|
   s.test_files    = `git ls-files -- {test,spec,features}/*`.split("\n")
   s.executables   = `git ls-files -- bin/*`.split("\n").map{ |f| File.basename(f) }
   s.require_paths = ["lib"]
+
+  s.add_runtime_dependency 'activesupport', ['>= 3.0.0']
 end
diff --git a/gemfiles/Gemfile-sinatra b/gemfiles/Gemfile-sinatra
new file mode 100644
index 0000000..96cc384
--- /dev/null
+++ b/gemfiles/Gemfile-sinatra
@@ -0,0 +1,13 @@
+source :rubygems
+
+gem 'active_decorator', :path => '../'
+
+gem 'sinatra', '>= 1.3'
+gem 'activerecord', '~> 3.2.0'
+gem 'padrino-helpers'
+gem 'rspec'
+gem 'rack-test'
+gem 'sinatra-contrib'
+gem 'capybara', '>= 2'
+gem 'sqlite3'
+gem 'rake'
diff --git a/lib/active_decorator.rb b/lib/active_decorator.rb
index 0d20e7a..75bb9fb 100644
--- a/lib/active_decorator.rb
+++ b/lib/active_decorator.rb
@@ -1,3 +1,12 @@
+begin
+  require 'rails'
+rescue LoadError
+  #do nothing
+end
+
 require 'active_decorator/version'
 require 'active_decorator/decorator'
-require 'active_decorator/railtie'
+
+if defined? Rails
+  require 'active_decorator/railtie'
+end
diff --git a/lib/active_decorator/monkey/sinatra.rb b/lib/active_decorator/monkey/sinatra.rb
new file mode 100644
index 0000000..b9c3f85
--- /dev/null
+++ b/lib/active_decorator/monkey/sinatra.rb
@@ -0,0 +1,29 @@
+module Sinatra
+  class Base
+    set :decorators, Proc.new { root && File.join(root, 'decorators') }
+    set :protected_instance_variables,
+      ActiveDecorator::Sinatra::DEFAULT_PROTECTED_INSTANCE_VARIABLES
+    
+    before do
+      ActiveDecorator::ViewContext.current = self
+    end
+  end
+  module Templates
+    def render_with_decorate(engine, data, options = {}, locals = {}, &block)
+      locals = options.delete(:locals) || locals || {}
+      locals.values.each do |v|
+        ActiveDecorator::Decorator.instance.decorate v
+      end
+
+      scope = options.delete(:scope) || self
+      ivars = scope.instance_variable_names - settings.protected_instance_variables
+      ivars.each do |n|
+        ActiveDecorator::Decorator.instance.decorate scope.instance_variable_get(n)
+      end
+      options[:scope] = scope
+
+      render_without_decorate(engine, data, options, locals, &block)
+    end
+    alias_method_chain :render, :decorate
+  end
+end
diff --git a/lib/active_decorator/sinatra.rb b/lib/active_decorator/sinatra.rb
new file mode 100644
index 0000000..801c339
--- /dev/null
+++ b/lib/active_decorator/sinatra.rb
@@ -0,0 +1,27 @@
+require 'sinatra/base'
+require 'active_decorator'
+require 'active_decorator/view_context'
+require 'active_support/core_ext/object'
+
+module ActiveDecorator
+  module Sinatra
+    DEFAULT_PROTECTED_INSTANCE_VARIABLES = %w[
+      @app @default_layout @env @params @preferred_extension
+      @request @response @template_cache
+    ].freeze
+
+    class << self
+      def registered(app)
+        app.class_eval do
+          Dir[File.join(settings.decorators, '**/*_decorator.rb')].each do |path|
+            require path
+          end
+        end
+      end
+
+      alias included registered
+    end
+  end
+end
+
+require 'active_decorator/monkey/sinatra'
diff --git a/lib/active_decorator/view_context.rb b/lib/active_decorator/view_context.rb
index cb1a2c6..5ad7a9c 100644
--- a/lib/active_decorator/view_context.rb
+++ b/lib/active_decorator/view_context.rb
@@ -1,3 +1,5 @@
+require 'active_support/concern'
+
 module ActiveDecorator
   module ViewContext
     class << self
diff --git a/spec/fake_app/decorators.rb b/spec/fake_app/decorators.rb
new file mode 100644
index 0000000..4cf2b32
--- /dev/null
+++ b/spec/fake_app/decorators.rb
@@ -0,0 +1,27 @@
+# decorators
+module AuthorDecorator
+  def reverse_name
+    name.reverse
+  end
+
+  def capitalized_name
+    name.capitalize
+  end
+end
+module BookDecorator
+  def reverse_title
+    title.reverse
+  end
+
+  def upcased_title
+    title.upcase
+  end
+
+  def link
+    link_to title, "#{request.protocol}#{request.host_with_port}/assets/sample.png"
+  end
+
+  def cover_image
+    image_tag 'cover.png'
+  end
+end
diff --git a/spec/fake_app/models.rb b/spec/fake_app/models.rb
new file mode 100644
index 0000000..d6c72b8
--- /dev/null
+++ b/spec/fake_app/models.rb
@@ -0,0 +1,15 @@
+# models
+class Author < ActiveRecord::Base
+  has_many :books
+end
+class Book < ActiveRecord::Base
+  belongs_to :author
+end
+
+# migrations
+class CreateAllTables < ActiveRecord::Migration
+  def self.up
+    create_table(:authors) {|t| t.string :name}
+    create_table(:books) {|t| t.string :title; t.references :author}
+  end
+end
diff --git a/spec/fake_app/fake_app.rb b/spec/fake_app/rails_app.rb
similarity index 59%
rename from spec/fake_app/fake_app.rb
rename to spec/fake_app/rails_app.rb
index ae9b00c..34a20ae 100644
--- a/spec/fake_app/fake_app.rb
+++ b/spec/fake_app/rails_app.rb
@@ -2,6 +2,9 @@
 require 'action_controller/railtie'
 require 'action_view/railtie'
 
+require 'fake_app/models'
+require 'fake_app/decorators'
+
 # config
 ActiveRecord::Base.establish_connection(:adapter => 'sqlite3', :database => ':memory:')
 
@@ -21,48 +24,12 @@ class Application < Rails::Application
   end
 end
 
-# models
-class Author < ActiveRecord::Base
-  has_many :books
-end
-class Book < ActiveRecord::Base
-  belongs_to :author
-end
-
 # helpers
 module ApplicationHelper; end
 
-# decorators
-module AuthorDecorator
-  def reverse_name
-    name.reverse
-  end
-
-  def capitalized_name
-    name.capitalize
-  end
-end
-module BookDecorator
-  def reverse_title
-    title.reverse
-  end
-
-  def upcased_title
-    title.upcase
-  end
-
-  def link
-    link_to title, "#{request.protocol}#{request.host_with_port}/assets/sample.png"
-  end
-
-  def cover_image
-    image_tag 'cover.png'
-  end
-end
-
 # controllers
 class ApplicationController < ActionController::Base
-  self.append_view_path File.dirname(__FILE__)
+  self.append_view_path File.dirname(__FILE__)+"/rails_views"
 end
 class AuthorsController < ApplicationController
   def index
@@ -82,11 +49,3 @@ def show
     @book = Author.find(params[:author_id]).books.find(params[:id])
   end
 end
-
-# migrations
-class CreateAllTables < ActiveRecord::Migration
-  def self.up
-    create_table(:authors) {|t| t.string :name}
-    create_table(:books) {|t| t.string :title; t.references :author}
-  end
-end
diff --git a/spec/fake_app/authors/index.html.erb b/spec/fake_app/rails_views/authors/index.html.erb
similarity index 100%
rename from spec/fake_app/authors/index.html.erb
rename to spec/fake_app/rails_views/authors/index.html.erb
diff --git a/spec/fake_app/authors/show.html.erb b/spec/fake_app/rails_views/authors/show.html.erb
similarity index 100%
rename from spec/fake_app/authors/show.html.erb
rename to spec/fake_app/rails_views/authors/show.html.erb
diff --git a/spec/fake_app/books/_book.html.erb b/spec/fake_app/rails_views/books/_book.html.erb
similarity index 100%
rename from spec/fake_app/books/_book.html.erb
rename to spec/fake_app/rails_views/books/_book.html.erb
diff --git a/spec/fake_app/books/_book_locals.html.erb b/spec/fake_app/rails_views/books/_book_locals.html.erb
similarity index 100%
rename from spec/fake_app/books/_book_locals.html.erb
rename to spec/fake_app/rails_views/books/_book_locals.html.erb
diff --git a/spec/fake_app/books/show.html.erb b/spec/fake_app/rails_views/books/show.html.erb
similarity index 100%
rename from spec/fake_app/books/show.html.erb
rename to spec/fake_app/rails_views/books/show.html.erb
diff --git a/spec/fake_app/sinatra_app.rb b/spec/fake_app/sinatra_app.rb
new file mode 100644
index 0000000..627ea93
--- /dev/null
+++ b/spec/fake_app/sinatra_app.rb
@@ -0,0 +1,41 @@
+require 'active_record'
+require 'sinatra/base'
+
+require 'fake_app/models'
+require 'fake_app/decorators'
+
+# config
+ActiveRecord::Base.establish_connection(:adapter => 'sqlite3', :database => ':memory:')
+
+class Sinatra::Request < Rack::Request
+  def protocol
+    scheme
+  end
+end
+
+class ActiveDecoratorSinatraTestApp < Sinatra::Base
+  register ActiveDecorator::Sinatra
+  set :views, File.dirname(__FILE__)+"/sinatra_views"
+
+  register Padrino::Helpers
+
+  get '/authors' do
+    if params[:variable_type] == 'array'
+      @authors = Author.all
+    else
+      @authors = Author.scoped
+    end
+
+    erb :'authors/index.html'
+  end
+
+  get '/authors/:id' do
+    @author = Author.find params[:id]
+    erb :'authors/show.html'
+  end
+
+  get '/authors/:author_id/books/:id' do
+    @book = Author.find(params[:author_id]).books.find(params[:id])
+    erb :'books/show.html'
+  end
+end
diff --git a/spec/fake_app/sinatra_views/authors/index.html.erb b/spec/fake_app/sinatra_views/authors/index.html.erb
new file mode 100644
index 0000000..2eb2137
--- /dev/null
+++ b/spec/fake_app/sinatra_views/authors/index.html.erb
@@ -0,0 +1,8 @@
+<% @authors.each do |author| %>
+  <%= author.name %>
+  <%= author.reverse_name %>
+
+  <% author.books.each do |book| %>
+    <%= erb :'books/_book_locals.html', :locals => {:b => book} %>
+  <% end %>
+<% end %>
diff --git a/spec/fake_app/sinatra_views/authors/show.html.erb b/spec/fake_app/sinatra_views/authors/show.html.erb
new file mode 100644
index 0000000..761ec66
--- /dev/null
+++ b/spec/fake_app/sinatra_views/authors/show.html.erb
@@ -0,0 +1,2 @@
+<%= @author.name %>
+<%= @author.capitalized_name %>
diff --git a/spec/fake_app/sinatra_views/books/_book.html.erb b/spec/fake_app/sinatra_views/books/_book.html.erb
new file mode 100644
index 0000000..2986258
--- /dev/null
+++ b/spec/fake_app/sinatra_views/books/_book.html.erb
@@ -0,0 +1,2 @@
+<%= book.title %>
+<%= book.reverse_title %>
diff --git a/spec/fake_app/sinatra_views/books/_book_locals.html.erb b/spec/fake_app/sinatra_views/books/_book_locals.html.erb
new file mode 100644
index 0000000..0b11f3d
--- /dev/null
+++ b/spec/fake_app/sinatra_views/books/_book_locals.html.erb
@@ -0,0 +1,2 @@
+<%= b.title %>
+<%= b.upcased_title %>
diff --git a/spec/fake_app/sinatra_views/books/show.html.erb b/spec/fake_app/sinatra_views/books/show.html.erb
new file mode 100644
index 0000000..c56015b
--- /dev/null
+++ b/spec/fake_app/sinatra_views/books/show.html.erb
@@ -0,0 +1,2 @@
+<%= @book.link %>
+<%= @book.cover_image %>
diff --git a/spec/features/partial_spec.rb b/spec/features/partial_spec.rb
index a5d1d22..6e30be4 100644
--- a/spec/features/partial_spec.rb
+++ b/spec/features/partial_spec.rb
@@ -11,13 +11,13 @@
     Author.delete_all
   end
 
-  scenario 'decorating implicit @object' do
+  scenario 'decorating implicit @object', :if => rails? do
     visit '/authors'
     page.should have_content 'the gc book'
     page.should have_content 'the gc book'.reverse
   end
 
-  scenario 'decorating implicit @collection' do
+  scenario 'decorating implicit @collection', :if => rails? do
     visit '/authors?partial=collection'
     page.should have_content 'the gc book'
     page.should have_content 'the gc book'.reverse
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 6a9c1bd..7995c76 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,11 +1,41 @@
 $LOAD_PATH.unshift(File.join(File.dirname(__FILE__), '..', 'lib'))
 $LOAD_PATH.unshift(File.dirname(__FILE__))
-# load Rails first
-require 'rails'
-require 'active_decorator'
-# needs to load the app before loading rspec/rails => capybara
-require 'fake_app/fake_app'
-require 'rspec/rails'
+
+begin
+  # load Rails first
+  require 'rails'
+rescue LoadError
+end
+
+require 'bundler/setup'
+Bundler.require
+
+require 'capybara/rspec'
+
+if defined? Rails
+  require 'active_decorator'
+  # needs to load the app before loading rspec/rails => capybara
+  require 'fake_app/rails_app'
+  require 'rspec/rails'
+
+  def rails?; true end
+end
+if defined? Sinatra
+  require 'active_decorator/sinatra'
+  require 'fake_app/sinatra_app'
+  require 'rack/test'
+  require 'sinatra/test_helpers'
+
+  def rails?; false end
+
+  Capybara.app = ActiveDecoratorSinatraTestApp
+
+  RSpec.configure do |config|
+    config.include Rack::Test::Methods
+    config.include Sinatra::TestHelpers
+  end
+end
+
 # Requires supporting files with custom matchers and macros, etc,
 # in ./support/ and its subdirectories.
 Dir["#{File.dirname(__FILE__)}/support/**/*.rb"].each {|f| require f}