diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index e13e3d7..21d0f52 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -295,6 +295,7 @@ Yii Framework 2 Change Log
 - New: Added `yii\web\GroupUrlRule` (qiangxue)
 - New: Added `yii\filters\RateLimiter` (qiangxue)
 - New: Added various authentication methods, including `HttpBasicAuth`, `HttpBearerAuth`, `QueryParamAuth`, and `CompositeAuth` (qiangxue)
+- New: Added `HtmlResponseFormatter` and `JsonResponseFormatter` (qiangxue)
 
 2.0.0-alpha, December 1, 2013
 -----------------------------
diff --git a/framework/web/HtmlResponseFormatter.php b/framework/web/HtmlResponseFormatter.php
new file mode 100644
index 0000000..623cab3
--- /dev/null
+++ b/framework/web/HtmlResponseFormatter.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\web;
+
+use yii\base\Component;
+
+/**
+ * HtmlResponseFormatter formats the given data into an HTML response content.
+ *
+ * It is used by [[Response]] to format response data.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class HtmlResponseFormatter extends Component implements ResponseFormatterInterface
+{
+    /**
+     * @var string the Content-Type header for the response
+     */
+    public $contentType = 'text/html';
+
+    /**
+     * Formats the specified response.
+     * @param Response $response the response to be formatted.
+     */
+    public function format($response)
+    {
+        if (stripos($this->contentType, 'charset') === false) {
+            $this->contentType .= '; charset=' . $response->charset;
+        }
+        $response->getHeaders()->set('Content-Type', $this->contentType);
+        $response->content = $response->data;
+    }
+}
diff --git a/framework/web/JsonResponseFormatter.php b/framework/web/JsonResponseFormatter.php
new file mode 100644
index 0000000..bd47704
--- /dev/null
+++ b/framework/web/JsonResponseFormatter.php
@@ -0,0 +1,68 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\web;
+
+use Yii;
+use yii\base\Component;
+use yii\helpers\Json;
+
+/**
+ * JsonResponseFormatter formats the given data into a JSON or JSONP response content.
+ *
+ * It is used by [[Response]] to format response data.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class JsonResponseFormatter extends Component implements ResponseFormatterInterface
+{
+    /**
+     * @var boolean whether to use JSONP response format. When this is true, the [[Response::data|response data]]
+     * must be an array consisting of `data` and `callback` members. The latter should be a JavaScript
+     * function name while the former will be passed to this function as a parameter.
+     */
+    public $useJsonp = false;
+
+     /**
+      * Formats the specified response.
+      * @param Response $response the response to be formatted.
+      */
+     public function format($response)
+     {
+         if ($this->useJsonp) {
+             $this->formatJsonp($response);
+         } else {
+             $this->formatJson($response);
+         }
+     }
+
+    /**
+     * Formats response data in JSON format.
+     * @param Response $response
+     */
+    protected function formatJson($response)
+    {
+        $response->getHeaders()->set('Content-Type', 'application/json; charset=UTF-8');
+        $response->content = Json::encode($response->data);
+    }
+
+    /**
+     * Formats response data in JSONP format.
+     * @param Response $response
+     */
+    protected function formatJsonp($response)
+    {
+        $response->getHeaders()->set('Content-Type', 'application/javascript; charset=UTF-8');
+        if (is_array($response->data) && isset($response->data['data'], $response->data['callback'])) {
+            $response->content = sprintf('%s(%s);', $response->data['callback'], Json::encode($response->data['data']));
+        } else {
+            $response->content = '';
+            Yii::warning("The 'jsonp' response requires that the data be an array consisting of both 'data' and 'callback' elements.", __METHOD__);
+        }
+    }
+}
diff --git a/framework/web/Response.php b/framework/web/Response.php
index 9b4232d..1dfc10d 100644
--- a/framework/web/Response.php
+++ b/framework/web/Response.php
@@ -12,7 +12,6 @@ use yii\base\InvalidConfigException;
 use yii\base\InvalidParamException;
 use yii\helpers\Url;
 use yii\helpers\FileHelper;
-use yii\helpers\Json;
 use yii\helpers\Security;
 use yii\helpers\StringHelper;
 
@@ -82,7 +81,8 @@ class Response extends \yii\base\Response
 
     /**
      * @var string the response format. This determines how to convert [[data]] into [[content]]
-     * when the latter is not set. By default, the following formats are supported:
+     * when the latter is not set. The value of this property must be one of the keys declared in the [[formatters] array.
+     * By default, the following formats are supported:
      *
      * - [[FORMAT_RAW]]: the data will be treated as the response content without any conversion.
      *   No extra HTTP header will be added.
@@ -102,12 +102,38 @@ class Response extends \yii\base\Response
      */
     public $format = self::FORMAT_HTML;
     /**
+     * @var array a list of supported response formats. The keys are MIME types (e.g. `application/json`)
+     * while the values are the corresponding formats (e.g. `html`, `json`) which must be supported by [[formatters]].
+     * When this property is set, a content type negotiation process will be conducted to determine
+     * the value of [[format]] and the corresponding [[mimeType]] and [[acceptParams]] values.
+     */
+    public $supportedFormats;
+    /**
+     * @var string the MIME type (e.g. `application/json`) chosen for this response after content type negotiation.
+     * This property will be set by the content type negotiation process.
+     */
+    public $mimeType;
+    /**
+     * @var array the parameters (e.g. `['q' => 1, 'version' => '1.0']`) for the MIME type chosen
+     * by the content type negotiation. This is a list of name-value pairs associated with [[mimeType]]
+     * from the ACCEPT HTTP header. This property will be set by the content type negotiation process.
+     */
+    public $acceptParams;
+    /**
      * @var array the formatters for converting data into the response content of the specified [[format]].
      * The array keys are the format names, and the array values are the corresponding configurations
      * for creating the formatter objects.
      * @see format
      */
-    public $formatters;
+    public $formatters = [
+        self::FORMAT_HTML => 'yii\web\HtmlResponseFormatter',
+        self::FORMAT_XML => 'yii\web\XmlResponseFormatter',
+        self::FORMAT_JSON => 'yii\web\JsonResponseFormatter',
+        self::FORMAT_JSONP => [
+            'class' => 'yii\web\HtmlResponseFormatter',
+            'useJsonp' => true,
+        ],
+    ];
     /**
      * @var mixed the original response data. When this is not null, it will be converted into [[content]]
      * according to [[format]] when the response is being sent out.
@@ -835,41 +861,17 @@ class Response extends \yii\base\Response
         if (isset($this->formatters[$this->format])) {
             $formatter = $this->formatters[$this->format];
             if (!is_object($formatter)) {
-                $formatter = Yii::createObject($formatter);
+                $this->formatters[$this->format] = $formatter = Yii::createObject($formatter);
             }
             if ($formatter instanceof ResponseFormatterInterface) {
                 $formatter->format($this);
             } else {
                 throw new InvalidConfigException("The '{$this->format}' response formatter is invalid. It must implement the ResponseFormatterInterface.");
             }
+        } elseif ($this->format === self::FORMAT_RAW) {
+            $this->content = $this->data;
         } else {
-            switch ($this->format) {
-                case self::FORMAT_HTML:
-                    $this->getHeaders()->setDefault('Content-Type', 'text/html; charset=' . $this->charset);
-                    $this->content = $this->data;
-                    break;
-                case self::FORMAT_RAW:
-                    $this->content = $this->data;
-                    break;
-                case self::FORMAT_JSON:
-                    $this->getHeaders()->set('Content-Type', 'application/json; charset=UTF-8');
-                    $this->content = Json::encode($this->data);
-                    break;
-                case self::FORMAT_JSONP:
-                    $this->getHeaders()->set('Content-Type', 'text/javascript; charset=' . $this->charset);
-                    if (is_array($this->data) && isset($this->data['data'], $this->data['callback'])) {
-                        $this->content = sprintf('%s(%s);', $this->data['callback'], Json::encode($this->data['data']));
-                    } else {
-                        $this->content = '';
-                        Yii::warning("The 'jsonp' response requires that the data be an array consisting of both 'data' and 'callback' elements.", __METHOD__);
-                    }
-                    break;
-                case self::FORMAT_XML:
-                    Yii::createObject(XmlResponseFormatter::className())->format($this);
-                    break;
-                default:
-                    throw new InvalidConfigException("Unsupported response format: {$this->format}");
-            }
+            throw new InvalidConfigException("Unsupported response format: {$this->format}");
         }
 
         if (is_array($this->content)) {
diff --git a/framework/web/XmlResponseFormatter.php b/framework/web/XmlResponseFormatter.php
index 594034b..b9766bc 100644
--- a/framework/web/XmlResponseFormatter.php
+++ b/framework/web/XmlResponseFormatter.php
@@ -51,8 +51,12 @@ class XmlResponseFormatter extends Component implements ResponseFormatterInterfa
      */
     public function format($response)
     {
+        $charset = $this->encoding === null ? $response->charset : $this->encoding;
+        if (stripos($this->contentType, 'charset') === false) {
+            $this->contentType .= '; charset=' . $charset;
+        }
         $response->getHeaders()->set('Content-Type', $this->contentType);
-        $dom = new DOMDocument($this->version, $this->encoding === null ? $response->charset : $this->encoding);
+        $dom = new DOMDocument($this->version, $charset);
         $root = new DOMElement($this->rootTag);
         $dom->appendChild($root);
         $this->buildXml($root, $response->data);