diff --git a/CRM/Utils/Hook.php b/CRM/Utils/Hook.php
index 12e595fb5cce..6ba3d50ccff6 100644
--- a/CRM/Utils/Hook.php
+++ b/CRM/Utils/Hook.php
@@ -1635,6 +1635,29 @@ public static function disable() {
     );
   }
 
+  /**
+   * Alter redirect.
+   *
+   * This hook is called when the browser is being re-directed and allows the url
+   * to be altered.
+   *
+   * @param \Psr\Http\Message\UriInterface $url
+   * @param string $outputFormat
+   *   The output format for the request. Generally this will be NULL or json.
+   *   If json it will lead to json output being returned rather than a true redirect.
+   * @param array $context
+   *   Optional additional information about context.
+   *
+   * @return null
+   *   the return value is ignored
+   */
+  public static function alterRedirect(&$url, &$outputFormat, $context) {
+    return self::singleton()->invoke(array('url', 'outputFormat', 'context'), $url,
+      $outputFormat, $context,
+      self::$_nullObject, self::$_nullObject, self::$_nullObject,
+      'civicrm_alterRedirect'
+    );
+  }
   /**
    * @param $varType
    * @param $var
diff --git a/CRM/Utils/System.php b/CRM/Utils/System.php
index a253b091c047..8ce4183320f6 100644
--- a/CRM/Utils/System.php
+++ b/CRM/Utils/System.php
@@ -433,8 +433,10 @@ public static function getClassName($object) {
    *
    * @param string $url
    *   The URL to provide to the browser via the Location header.
+   * @param array $context
+   *   Optional additional information for the hook.
    */
-  public static function redirect($url = NULL) {
+  public static function redirect($url = NULL, $context = []) {
     if (!$url) {
       $url = self::url('civicrm/dashboard', 'reset=1');
     }
@@ -442,8 +444,14 @@ public static function redirect($url = NULL) {
     // this is kinda hackish but not sure how to do it right
     $url = str_replace('&', '&', $url);
 
+    $output = CRM_Utils_Array::value('snippet', $_GET);
+
+    $parsedUrl = CRM_Utils_Url::parseUrl($url);
+    CRM_Utils_Hook::alterRedirect($parsedUrl, $context, $output);
+    $url = CRM_Utils_Url::unparseUrl($parsedUrl);
+
     // If we are in a json context, respond appropriately
-    if (CRM_Utils_Array::value('snippet', $_GET) === 'json') {
+    if ($output === 'json') {
       CRM_Core_Page_AJAX::returnJsonResponse(array(
         'status' => 'redirect',
         'userContext' => $url,
diff --git a/CRM/Utils/Url.php b/CRM/Utils/Url.php
new file mode 100644
index 000000000000..00e28be4790b
--- /dev/null
+++ b/CRM/Utils/Url.php
@@ -0,0 +1,55 @@
+<?php
+/*
+ +--------------------------------------------------------------------+
+ | CiviCRM version 4.7                                                |
+ +--------------------------------------------------------------------+
+ | Copyright CiviCRM LLC (c) 2004-2017                                |
+ +--------------------------------------------------------------------+
+ | This file is a part of CiviCRM.                                    |
+ |                                                                    |
+ | CiviCRM is free software; you can copy, modify, and distribute it  |
+ | under the terms of the GNU Affero General Public License           |
+ | Version 3, 19 November 2007 and the CiviCRM Licensing Exception.   |
+ |                                                                    |
+ | CiviCRM is distributed in the hope that it will be useful, but     |
+ | WITHOUT ANY WARRANTY; without even the implied warranty of         |
+ | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.               |
+ | See the GNU Affero General Public License for more details.        |
+ |                                                                    |
+ | You should have received a copy of the GNU Affero General Public   |
+ | License and the CiviCRM Licensing Exception along                  |
+ | with this program; if not, contact CiviCRM LLC                     |
+ | at info[AT]civicrm[DOT]org. If you have questions about the        |
+ | GNU Affero General Public License or the licensing of CiviCRM,     |
+ | see the CiviCRM license FAQ at http://civicrm.org/licensing        |
+ +--------------------------------------------------------------------+
+ */
+
+use GuzzleHttp\Psr7\Uri;
+use Psr\Http\Message\UriInterface;
+
+class CRM_Utils_Url {
+
+  /**
+   * Parse url to a UriInterface.
+   *
+   * @param string $url
+   *
+   * @return UriInterface
+   */
+  public static function parseUrl($url) {
+    return new Uri($url);
+  }
+
+  /**
+   * Unparse url back to a string.
+   *
+   * @param UriInterface $parsed
+   *
+   * @return string
+   */
+  static public function unparseUrl(UriInterface $parsed) {
+    return $parsed->__toString();
+  }
+
+}
diff --git a/composer.json b/composer.json
index 5ac5d6427dad..0d4f738486c8 100644
--- a/composer.json
+++ b/composer.json
@@ -54,7 +54,8 @@
     "pear/Auth_SASL": "1.1.0",
     "pear/Net_SMTP": "1.6.*",
     "pear/Net_socket": "1.0.*",
-    "civicrm/civicrm-setup": "~0.2.0"
+    "civicrm/civicrm-setup": "~0.2.0",
+    "guzzlehttp/guzzle": "^5.3"
   },
   "repositories": [
     {
diff --git a/composer.lock b/composer.lock
index 7a81794d0534..76ea8c5c7eea 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
     ],
-    "content-hash": "3aaaa7a6146043643e9fe2cbc8030cca",
+    "content-hash": "cdda1c006828ed2eac0bddcc7192fc37",
     "packages": [
         {
             "name": "civicrm/civicrm-cxn-rpc",
@@ -182,6 +182,160 @@
             "homepage": "http://code.google.com/p/phpquery/",
             "time": "2013-03-21T12:39:33+00:00"
         },
+        {
+            "name": "guzzlehttp/guzzle",
+            "version": "5.3.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/guzzle/guzzle.git",
+                "reference": "f9acb4761844317e626a32259205bec1f1bc60d2"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/guzzle/guzzle/zipball/f9acb4761844317e626a32259205bec1f1bc60d2",
+                "reference": "f9acb4761844317e626a32259205bec1f1bc60d2",
+                "shasum": ""
+            },
+            "require": {
+                "guzzlehttp/ringphp": "^1.1",
+                "php": ">=5.4.0",
+                "react/promise": "^2.2"
+            },
+            "require-dev": {
+                "ext-curl": "*",
+                "phpunit/phpunit": "^4.0"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "GuzzleHttp\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                }
+            ],
+            "description": "Guzzle is a PHP HTTP client library and framework for building RESTful web service clients",
+            "homepage": "http://guzzlephp.org/",
+            "keywords": [
+                "client",
+                "curl",
+                "framework",
+                "http",
+                "http client",
+                "rest",
+                "web service"
+            ],
+            "time": "2018-01-15T07:18:01+00:00"
+        },
+        {
+            "name": "guzzlehttp/ringphp",
+            "version": "1.1.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/guzzle/RingPHP.git",
+                "reference": "dbbb91d7f6c191e5e405e900e3102ac7f261bc0b"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/guzzle/RingPHP/zipball/dbbb91d7f6c191e5e405e900e3102ac7f261bc0b",
+                "reference": "dbbb91d7f6c191e5e405e900e3102ac7f261bc0b",
+                "shasum": ""
+            },
+            "require": {
+                "guzzlehttp/streams": "~3.0",
+                "php": ">=5.4.0",
+                "react/promise": "~2.0"
+            },
+            "require-dev": {
+                "ext-curl": "*",
+                "phpunit/phpunit": "~4.0"
+            },
+            "suggest": {
+                "ext-curl": "Guzzle will use specific adapters if cURL is present"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.1-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "GuzzleHttp\\Ring\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                }
+            ],
+            "description": "Provides a simple API and specification that abstracts away the details of HTTP into a single PHP function.",
+            "time": "2015-05-20T03:37:09+00:00"
+        },
+        {
+            "name": "guzzlehttp/streams",
+            "version": "3.0.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/guzzle/streams.git",
+                "reference": "47aaa48e27dae43d39fc1cea0ccf0d84ac1a2ba5"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/guzzle/streams/zipball/47aaa48e27dae43d39fc1cea0ccf0d84ac1a2ba5",
+                "reference": "47aaa48e27dae43d39fc1cea0ccf0d84ac1a2ba5",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.4.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~4.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "3.0-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "GuzzleHttp\\Stream\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                }
+            ],
+            "description": "Provides a simple abstraction over streams of data",
+            "homepage": "http://guzzlephp.org/",
+            "keywords": [
+                "Guzzle",
+                "stream"
+            ],
+            "time": "2014-10-12T19:18:40+00:00"
+        },
         {
             "name": "marcj/topsort",
             "version": "dev-1.0-php53",
@@ -890,6 +1044,52 @@
             ],
             "time": "2012-12-21T11:40:51+00:00"
         },
+        {
+            "name": "react/promise",
+            "version": "v2.5.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/reactphp/promise.git",
+                "reference": "62785ae604c8d69725d693eb370e1d67e94c4053"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/reactphp/promise/zipball/62785ae604c8d69725d693eb370e1d67e94c4053",
+                "reference": "62785ae604c8d69725d693eb370e1d67e94c4053",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.4.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~4.8"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "React\\Promise\\": "src/"
+                },
+                "files": [
+                    "src/functions_include.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Jan Sorgalla",
+                    "email": "jsorgalla@gmail.com"
+                }
+            ],
+            "description": "A lightweight implementation of CommonJS Promises/A for PHP",
+            "keywords": [
+                "promise",
+                "promises"
+            ],
+            "time": "2017-03-25T12:08:31+00:00"
+        },
         {
             "name": "sabberworm/php-css-parser",
             "version": "6.0.1",
diff --git a/tests/phpunit/CRM/Utils/SystemTest.php b/tests/phpunit/CRM/Utils/SystemTest.php
index 2874bfe873da..f4223d4c9c4c 100644
--- a/tests/phpunit/CRM/Utils/SystemTest.php
+++ b/tests/phpunit/CRM/Utils/SystemTest.php
@@ -35,4 +35,73 @@ public function testEvalUrl() {
     $this->assertEquals('http://example.com/?cms=UnitTests', CRM_Utils_System::evalUrl('http://example.com/?cms={uf}'));
   }
 
+  /**
+   * Test the redirect hook.
+   *
+   * @param string $url
+   * @param array $parsedUrl
+   *
+   * @dataProvider getURLs
+   */
+  public function testRedirectHook($url, $parsedUrl) {
+    $this->hookClass->setHook('civicrm_alterRedirect', array($this, 'hook_checkUrl'));
+    try {
+      CRM_Utils_System::redirect($url, [
+        'expected' => $parsedUrl,
+        'original' => $url
+      ]);
+    }
+    catch (CRM_Core_Exception $e) {
+      $this->assertEquals(ts('hook called'), $e->getMessage());
+      return;
+    }
+    $this->fail('Exception should have been thrown if hook was called');
+  }
+
+  /**
+   * Hook for alterRedirect.
+   *
+   * We do some checks here.
+   *
+   * @param array $urlQuery
+   * @param array $context
+   *
+   * @throws \CRM_Core_Exception
+   */
+  public function hook_checkUrl($urlQuery, $context) {
+    $this->assertEquals($context['expected'], $urlQuery);
+    $this->assertEquals($context['original'], CRM_Utils_Url::unparseUrl($urlQuery));
+    throw new CRM_Core_Exception(ts('hook called'));
+  }
+
+  /**
+   * Get urls for testing.
+   *
+   * @return array
+   */
+  public function getURLs() {
+    return [
+      ['https://example.com?ab=cd', [
+        'scheme' => 'https',
+        'host' => 'example.com',
+        'query' => ['ab' => 'cd'],
+      ]],
+      ['http://myuser:mypass@foo.bar:123/whiz?a=b&c=d', [
+          'scheme' => 'http',
+          'host' => 'foo.bar',
+          'port' => 123,
+          'user' => 'myuser',
+          'pass' => 'mypass',
+          'path' => '/whiz',
+          'query' => [
+              'a' => 'b',
+              'c' => 'd',
+          ],
+      ]],
+      ['/foo/bar', [
+        'path' => '/foo/bar'
+      ]],
+    ];
+  }
+
 }
diff --git a/tests/phpunit/CRM/Utils/UrlTest.php b/tests/phpunit/CRM/Utils/UrlTest.php
new file mode 100644
index 000000000000..0021bfd9b682
--- /dev/null
+++ b/tests/phpunit/CRM/Utils/UrlTest.php
@@ -0,0 +1,84 @@
+<?php
+
+use Psr\Http\Message\UriInterface;
+
+/**
+ * Class CRM_Utils_UrlTest
+ * @group headless
+ */
+class CRM_Utils_URLTest extends CiviUnitTestCase {
+
+  public function setUp() {
+    parent::setUp();
+  }
+
+  /**
+   * Test the redirect hook.
+   *
+   * @param string $url
+   * @param array $parsedUrl
+   *
+   * @dataProvider getURLs
+   */
+  public function testRedirectHook($url, $parsedUrl) {
+    $this->hookClass->setHook('civicrm_alterRedirect', array($this, 'hook_checkUrl'));
+    try {
+      CRM_Utils_System::redirect($url, [
+        'expected' => $parsedUrl,
+        'original' => $url
+      ]);
+    }
+    catch (CRM_Core_Exception $e) {
+      $this->assertEquals(ts('hook called'), $e->getMessage());
+      return;
+    }
+    $this->fail('Exception should have been thrown if hook was called');
+  }
+
+  /**
+   * Hook for alterRedirect.
+   *
+   * We do some checks here.
+   *
+   * @param UriInterface $urlQuery
+   * @param array $context
+   *
+   * @throws \CRM_Core_Exception
+   */
+  public function hook_checkUrl($urlQuery, $context) {
+    $this->assertEquals(CRM_Utils_Array::value('scheme', $context['expected']), $urlQuery->getScheme());
+    $this->assertEquals(CRM_Utils_Array::value('host', $context['expected']), $urlQuery->getHost());
+    $this->assertEquals(CRM_Utils_Array::value('query', $context['expected']), $urlQuery->getQuery());
+    $this->assertEquals($context['original'], CRM_Utils_Url::unparseUrl($urlQuery));
+
+    throw new CRM_Core_Exception(ts('hook called'));
+  }
+
+  /**
+   * Get urls for testing.
+   *
+   * @return array
+   */
+  public function getURLs() {
+    return [
+      ['https://example.com?ab=cd', [
+        'scheme' => 'https',
+        'host' => 'example.com',
+        'query' => 'ab=cd',
+      ]],
+      ['http://myuser:mypass@foo.bar:123/whiz?a=b&c=d', [
+          'scheme' => 'http',
+          'host' => 'foo.bar',
+          'port' => 123,
+          'user' => 'myuser',
+          'pass' => 'mypass',
+          'path' => '/whiz',
+          'query' => 'a=b&c=d',
+      ]],
+      ['/foo/bar', [
+        'path' => '/foo/bar'
+      ]],
+    ];
+  }
+
+}