diff --git a/lib/remarkable_mongomapper.rb b/lib/remarkable_mongomapper.rb
index 4c3090e..98be619 100644
--- a/lib/remarkable_mongomapper.rb
+++ b/lib/remarkable_mongomapper.rb
@@ -14,7 +14,9 @@
 Remarkable.add_locale File.join(dir, '..', 'locales', 'en.yml')
 
 require File.join(dir, 'remarkable_mongomapper', 'base')
- 
+require File.join(dir, 'remarkable_mongomapper', 'describe')
+# require File.join(dir, 'remarkable_mongomapper', 'human_names')
+
 # Add matchers
 Dir[File.join(dir, 'remarkable_mongomapper', 'matchers', '*.rb')].each do |file|
   require file
diff --git a/lib/remarkable_mongomapper/describe.rb b/lib/remarkable_mongomapper/describe.rb
new file mode 100644
index 0000000..18d2d21
--- /dev/null
+++ b/lib/remarkable_mongomapper/describe.rb
@@ -0,0 +1,199 @@
+module Remarkable
+  module ActiveRecord
+
+    def self.after_include(target) #:nodoc:
+      target.class_inheritable_reader :describe_subject_attributes, :default_subject_attributes
+      target.send :include, Describe
+    end
+
+    # Overwrites describe to provide quick way to configure your subject:
+    #
+    #   describe Post
+    #     should_validate_presente_of :title
+    #
+    #     describe :published => true do
+    #       should_validate_presence_of :published_at
+    #     end
+    #   end
+    #
+    # This is the same as:
+    #
+    #   describe Post
+    #     should_validate_presente_of :title
+    #
+    #     describe "when published is true" do
+    #       subject { Post.new(:published => true) }
+    #       should_validate_presence_of :published_at
+    #     end
+    #   end
+    #
+    # The string can be localized using I18n. An example yml file is:
+    #
+    #   locale:
+    #     remarkable:
+    #       mongo_mapper:
+    #         describe:
+    #           each: "{{key}} is {{value}}"
+    #           prepend: "when "
+    #           connector: " and "
+    #
+    # You can also call subject attributes to set the default attributes for a
+    # subject. You can even mix with a fixture replacement tool:
+    #
+    #   describe Post
+    #     # Fixjour example
+    #     subject_attributes { valid_post_attributes }
+    #
+    #     describe :published => true do
+    #       should_validate_presence_of :published_at
+    #     end
+    #   end
+    #
+    # You can retrieve the merged result of all attributes given using the
+    # subject_attributes instance method:
+    #
+    #   describe Post
+    #     # Fixjour example
+    #     subject_attributes { valid_post_attributes }
+    #
+    #     describe :published => true do
+    #       it "should have default subject attributes" do
+    #         subject_attributes.should == { :title => 'My title', :published => true }
+    #       end
+    #     end
+    #   end
+    #
+    module Describe
+
+      def self.included(base) #:nodoc:
+        base.extend ClassMethods
+      end
+
+      module ClassMethods
+
+        # Overwrites describe to provide quick way to configure your subject:
+        #
+        #   describe Post
+        #     should_validate_presente_of :title
+        #
+        #     describe :published => true do
+        #       should_validate_presence_of :published_at
+        #     end
+        #   end
+        #
+        # This is the same as:
+        #
+        #   describe Post
+        #     should_validate_presente_of :title
+        #
+        #     describe "when published is true" do
+        #       subject { Post.new(:published => true) }
+        #       should_validate_presence_of :published_at
+        #     end
+        #   end
+        #
+        # The string can be localized using I18n. An example yml file is:
+        #
+        #   locale:
+        #     remarkable:
+        #       mongo_mapper:
+        #         describe:
+        #           each: "{{key}} is {{value}}"
+        #           prepend: "when "
+        #           connector: " and "
+        #
+        # See also subject_attributes instance and class methods for more
+        # information.
+        #
+        def describe(*args, &block)
+          if described_class && args.first.is_a?(Hash)
+            attributes = args.shift
+
+            connector = Remarkable.t "remarkable.mongo_mapper.describe.connector", :default => " and "
+
+            description = if self.describe_subject_attributes.blank?
+              Remarkable.t("remarkable.mongo_mapper.describe.prepend", :default => "when ")
+            else
+              connector.lstrip
+            end
+
+            pieces = []
+            attributes.each do |key, value|
+              translated_key = if described_class.respond_to?(:human_attribute_name)
+                described_class.human_attribute_name(key.to_s, :locale => Remarkable.locale)
+              else
+                key.to_s.humanize
+              end
+
+              pieces << Remarkable.t("remarkable.mongo_mapper.describe.each",
+                                      :default => "{{key}} is {{value}}",
+                                      :key => translated_key.downcase, :value => value.inspect)
+            end
+
+            description << pieces.join(connector)
+            args.unshift(description)
+
+            # Creates an example group, set the subject and eval the given block.
+            #
+            example_group = super(*args) do
+              write_inheritable_hash(:describe_subject_attributes, attributes)
+              set_described_subject!
+              instance_eval(&block)
+            end
+          else
+            super(*args, &block)
+          end
+        end
+
+        # Sets default attributes for the subject. You can use this to set up
+        # your subject with valid attributes. You can even mix with a fixture
+        # replacement tool and still use quick subjects:
+        #
+        #   describe Post
+        #     # Fixjour example
+        #     subject_attributes { valid_post_attributes }
+        #
+        #     describe :published => true do
+        #       should_validate_presence_of :published_at
+        #     end
+        #   end
+        #
+        def subject_attributes(options=nil, &block)
+          write_inheritable_attribute(:default_subject_attributes, options || block)
+          set_described_subject!
+        end
+
+        def set_described_subject!
+          subject {
+            record = self.class.described_class.new
+            record.send(:attributes=, subject_attributes, false)
+            record
+          }
+        end
+      end
+
+      # Returns a hash with the subject attributes declared using the
+      # subject_attributes class method and the attributes given using the
+      # describe method.
+      #
+      #   describe Post
+      #     subject_attributes { valid_post_attributes }
+      #
+      #     describe :published => true do
+      #       it "should have default subject attributes" do
+      #         subject_attributes.should == { :title => 'My title', :published => true }
+      #       end
+      #     end
+      #   end
+      #
+      def subject_attributes
+        default = self.class.default_subject_attributes
+        default = self.instance_eval(&default) if default.is_a?(Proc)
+        default ||= {}
+
+        default.merge(self.class.describe_subject_attributes || {})
+      end
+
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/remarkable_mongomapper/human_names.rb b/lib/remarkable_mongomapper/human_names.rb
new file mode 100644
index 0000000..3d1c8a4
--- /dev/null
+++ b/lib/remarkable_mongomapper/human_names.rb
@@ -0,0 +1,37 @@
+if defined?(Spec)
+  module Spec #:nodoc:
+    module Example #:nodoc:
+      module ExampleGroupMethods #:nodoc:
+
+        # This allows "describe User" to use the I18n human name of User.
+        #
+        def self.build_description_with_i18n(*args)
+          args.inject("") do |description, arg|
+            arg = if arg.respond_to?(:human_name)
+              arg.human_name(:locale => Remarkable.locale)
+            else
+              arg.to_s
+            end
+
+            description << " " unless (description == "" || arg =~ /^(\s|\.|#)/)
+            description << arg
+          end
+        end
+
+        # This is for rspec <= 1.1.12.
+        #
+        def self.description_text(*args)
+          self.build_description_with_i18n(*args)
+        end
+
+        # This is for rspec >= 1.2.0.
+        #
+        def self.build_description_from(*args)
+          text = ExampleGroupMethods.build_description_with_i18n(*args)
+          text == "" ? nil : text
+        end
+
+      end
+    end
+  end
+end
diff --git a/spec/matchers/allow_values_for_matcher_spec.rb b/spec/matchers/allow_values_for_matcher_spec.rb
index 25bed83..24b9e3c 100644
--- a/spec/matchers/allow_values_for_matcher_spec.rb
+++ b/spec/matchers/allow_values_for_matcher_spec.rb
@@ -1,12 +1,24 @@
 require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
 
 describe 'allow_values_for' do
-  subject do
-    Site.new
+  include ModelBuilder
+
+  # Defines a model, create a validation and returns a raw matcher
+  def define_and_validate(options={})
+    @model = define_model :product do
+      include MongoMapper::Document
+      
+      key :title, String
+      key :category, String
+      
+      validates_format_of :title, options
+    end
+
+    allow_values_for(:title)
   end
 
   describe 'messages' do
-    before(:each){ @model = subject; @matcher = allow_values_for(:title) }
+    before(:each){ @matcher = define_and_validate(:with => /X|Y|Z/) }
 
     it 'should contain a description' do
       @matcher = allow_values_for(:title, "X", "Y", "Z")
@@ -15,40 +27,44 @@
 
     it 'should set is_valid? message' do
       @matcher.in("A").matches?(subject)
-      @matcher.failure_message.should == 'Expected Site to be valid when title is set to "A"'
+      @matcher.failure_message.should == 'Expected Product to be valid when title is set to "A"'
     end
 
     it 'should set allow_nil? message' do
       @matcher.allow_nil.matches?(subject)
-      @matcher.failure_message.should == 'Expected Site to allow nil values for title'
+      @matcher.failure_message.should == 'Expected Product to allow nil values for title'
     end
 
     it 'should set allow_blank? message' do
       @matcher.allow_blank.matches?(subject)
-      @matcher.failure_message.should == 'Expected Site to allow blank values for title'
+      @matcher.failure_message.should == 'Expected Product to allow blank values for title'
     end
   end
 
   describe 'matchers' do
-    it { should allow_values_for(:title).in('X', 'Y', 'Z') }
-    it { should_not allow_values_for(:title).in('A') }
+    it { should define_and_validate(:with => /X|Y|Z/).in('X', 'Y', 'Z') }
+    it { should_not define_and_validate(:with => /X|Y|Z/).in('A') }
   
-    # it { should define_and_validate(:with => /X|Y|Z/, :message => 'valid').in('X', 'Y', 'Z').message('valid') }
+    it { should define_and_validate(:with => /X|Y|Z/, :message => 'valid').in('X', 'Y', 'Z').message('valid') }
   
-    # create_optional_boolean_specs(:allow_nil, self, :with => /X|Y|Z/)
-    # create_optional_boolean_specs(:allow_blank, self, :with => /X|Y|Z/)
+    create_optional_boolean_specs(:allow_nil, self, :with => /X|Y|Z/)
+    create_optional_boolean_specs(:allow_blank, self, :with => /X|Y|Z/)
   end
   
   describe 'macros' do
+    before(:each){ define_and_validate(:with => /X|Y|Z/) }
+    
     should_allow_values_for :title, 'X'
     should_not_allow_values_for :title, 'A'
   end
   
   describe 'failures' do
     it "should fail if any of the values are valid on invalid cases" do
+      define_and_validate(:with => /X|Y|Z/)
+      
       lambda {
-        should_not allow_values_for :title, 'A', 'X', 'B'
-      }.should raise_error(Spec::Expectations::ExpectationNotMetError, /Did not expect Site to be valid/)
+        should_not allow_values_for(:title, 'A', 'X', 'B')
+      }.should raise_error(Spec::Expectations::ExpectationNotMetError, /Did not expect Product to be valid/)
     end
   end
 end
diff --git a/spec/model_builder.rb b/spec/model_builder.rb
new file mode 100644
index 0000000..e201fe6
--- /dev/null
+++ b/spec/model_builder.rb
@@ -0,0 +1,64 @@
+# This is based on Shoulda model builder for Test::Unit.
+#
+module ModelBuilder
+  def self.included(base)
+    return unless base.name =~ /^Spec/
+
+    base.class_eval do
+      after(:each) do
+        if @defined_constants
+          @defined_constants.each do |class_name| 
+            Object.send(:remove_const, class_name)
+          end
+        end
+      end
+    end
+
+    base.extend ClassMethods
+  end
+
+  def define_constant(class_name, &block)
+    class_name = class_name.to_s.camelize
+
+    klass = Class.new
+    Object.const_set(class_name, klass)
+
+    klass.class_eval(&block) if block_given?
+
+    @defined_constants ||= []
+    @defined_constants << class_name
+
+    klass
+  end
+
+  def define_model(name, columns = {}, &block)
+    instance = define_constant(name.to_s.classify, &block).new
+
+    self.class.subject { instance } if self.class.respond_to?(:subject)
+    instance
+  end
+
+  module ClassMethods
+    # This is a macro to run validations of boolean optionals such as :allow_nil
+    # and :allow_blank. This macro tests all scenarios. The specs must have a
+    # define_and_validate method defined.
+    #
+    def create_optional_boolean_specs(optional, base, options={})
+      base.describe "with #{optional} option" do
+        it { should define_and_validate(options.merge(optional => true)).send(optional)            }
+        it { should define_and_validate(options.merge(optional => false)).send(optional, false)    }
+        it { should_not define_and_validate(options.merge(optional => true)).send(optional, false) }
+        it { should_not define_and_validate(options.merge(optional => false)).send(optional)       }
+      end
+    end
+
+    def create_message_specs(base)
+      base.describe "with message option" do
+        it { should define_and_validate(:message => 'valid_message').message('valid_message') }
+        it { should_not define_and_validate(:message => 'not_valid').message('valid_message') }
+      end
+    end
+  end
+
+end
+
diff --git a/spec/models.rb b/spec/models.rb
index 9ddfb86..dc9930f 100644
--- a/spec/models.rb
+++ b/spec/models.rb
@@ -35,8 +35,6 @@ class Rating
 
 class Site
   include MongoMapper::Document
-  
-  key :title, String, :format => /X|Y|Z/
 end
 
 class Webiste
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 2aa50a0..afe9c0d 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -15,4 +15,5 @@ def reset_test_db!
 end
 
 require File.join(File.dirname(__FILE__), "..", "lib", "remarkable_mongomapper")
-require File.join(File.dirname(__FILE__), "models")
\ No newline at end of file
+require File.join(File.dirname(__FILE__), "models")
+require File.join(File.dirname(__FILE__), "model_builder")
\ No newline at end of file