diff --git a/lib/httparty.rb b/lib/httparty.rb
index bffac7c3..04344b74 100644
--- a/lib/httparty.rb
+++ b/lib/httparty.rb
@@ -494,10 +494,17 @@ def default_options #:nodoc:
 
       def perform_request(http_method, path, options, &block) #:nodoc:
         options = default_options.merge(options)
+        process_headers(options)
         process_cookies(options)
         Request.new(http_method, path, options).perform(&block)
       end
 
+      def process_headers(options)
+        if options[:headers] && headers.any?
+          options[:headers] = headers.merge(options[:headers])
+        end
+      end
+
       def process_cookies(options) #:nodoc:
         return unless options[:cookies] || default_cookies.any?
         options[:headers] ||= headers.dup
diff --git a/spec/httparty/httparty_spec.rb b/spec/httparty/httparty_spec.rb
new file mode 100644
index 00000000..d30d147b
--- /dev/null
+++ b/spec/httparty/httparty_spec.rb
@@ -0,0 +1,51 @@
+require File.expand_path(File.join(File.dirname(__FILE__), '..', 'spec_helper'))
+
+describe HTTParty do
+
+  class SimpleClient
+    include HTTParty
+  end
+
+  class HeadersClient
+    include HTTParty
+    headers "Accept" => "application/json"
+  end
+
+  def request
+    FakeWeb.last_request
+  end
+
+  context 'request headers' do
+
+    before do
+      @headers = { "User-Agent" => 'my-ruby', 'Content-Type' => 'text/plain' }
+      @uri = "http://localhost/request_headers"
+      FakeWeb.register_uri(:get, @uri, :body => "OK")
+    end
+
+    it 'should correctly set the request headers' do
+      SimpleClient.get(@uri, :headers => @headers)
+      @headers.each do |name, value|
+        request[name].should == value
+      end
+    end
+
+    it 'should correctly mix the current request and default headers' do
+      HeadersClient.get(@uri, :headers => @headers)
+      @headers.each do |name, value|
+        request[name].should == value
+      end
+      request['Accept'].should == 'application/json'
+    end
+
+    it 'should correctly override default headers with request headers' do
+      HeadersClient.get(@uri, :headers => @headers.merge('Accept' => 'text/html'))
+      @headers.each do |name, value|
+        request[name].should == value
+      end
+      request['Accept'].should == 'text/html'
+    end
+
+  end
+
+end
\ No newline at end of file
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index a7aeb9a5..9db324d0 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,4 +1,5 @@
 $:.push File.expand_path("../lib", __FILE__)
+
 require "httparty"
 
 require 'spec/autorun'