diff --git a/README.md b/README.md
index 566ed7d..23413d7 100644
--- a/README.md
+++ b/README.md
@@ -128,6 +128,8 @@ Note that the kind of value passed to the "id" key may vary depending on what se
 
 _**RegexSelector** uses <http://php.net/manual/en/function.preg-match-all.php> under the hood._
 
+For your convenience, when using Regex, a match with `'id' => 0` will return the URL of the crawled page.
+
 ### Retrieving & Sorting
 
 Once you've specified a selector using the **with** method, you can start retrieving and/or sorting the data.
@@ -188,18 +190,18 @@ $matches->filter(function($match) {
 
 ### Mutating
 
-In order to handle inconsistencies or formatting issues, you can alter the matched values to a more desirable value. Altering happens before filtering and sorting the result set. You can do so by using the `apply` index in the match configuration array with a closure that takes 1 argument: the matched value.
+In order to handle inconsistencies or formatting issues, you can alter the matched values to a more desirable value. Altering happens before filtering and sorting the result set. You can do so by using the `apply` index in the match configuration array with a closure that takes 2 arguments: the matched value and the URL of the crawled page.
 
 ```php
 $matchConfig = array(
     array(
         'name' => 'url',
         'id' => 1,
-        // Add domain to URL if it's not present already
-        'apply' => function($match) use($url)
+        // Add domain to relative URLs
+        'apply' => function($match, $sourceUrl)
         {
             if (!stristr($match, 'http')) {
-                return $url . trim($match, '/');
+                return $sourceUrl . trim($match, '/');
             }
             return $match;
         },
@@ -218,7 +220,7 @@ $matchConfig = array(
 
 ### Validation
 
-You may validate the matched data to insure that the result set always contains the desired result. Validation happens after optionally mutating the data set with `apply`. To add the validation rules that should be applied to the data, use the `validate` index in the match configuration array with a closure that takes one argument: the matched value. The closure should return `true` if the validation succeeded, and `false` if the validation failed. Matches that fail the validation will be removed from the result set.
+You may validate the matched data to insure that the result set always contains the desired result. Validation happens after optionally mutating the data set with `apply`. To add the validation rules that should be applied to the data, use the `validate` index in the match configuration array with a closure that takes 2 arguments: the matched value and the URL of the crawled page. The closure should return `true` if the validation succeeded, and `false` if the validation failed. Matches that fail the validation will be removed from the result set.
 
 ```php
 $matchConfig = array(
diff --git a/src/Laurentvw/Scrapher/Matcher.php b/src/Laurentvw/Scrapher/Matcher.php
index 8931eef..989f663 100644
--- a/src/Laurentvw/Scrapher/Matcher.php
+++ b/src/Laurentvw/Scrapher/Matcher.php
@@ -101,13 +101,15 @@ public function addLog($msg)
     /**
      * @param $content
      *
+     * @param $sourceKey
      * @return array
      */
-    public function getMatches($content)
+    public function getMatches($content, $sourceKey)
     {
         $filteredResults = array();
 
         $this->getSelector()->setContent($content);
+        $this->getSelector()->setSourceKey($sourceKey);
 
         $matches = $this->getSelector()->getMatches();
 
@@ -140,14 +142,14 @@ private function fetch(array $matchLine)
         foreach ($this->getSelector()->getConfig() as $match) {
             // Get the match value, optionally apply a function to it
             if (isset($match['apply'])) {
-                $result[$match['name']] = $match['apply']($matchLine[$match['name']]);
+                $result[$match['name']] = $match['apply']($matchLine[$match['name']], $this->getSelector()->getSourceKey());
             } else {
                 $result[$match['name']] = $matchLine[$match['name']];
             }
 
             // Validate this match
             if (isset($match['validate'])) {
-                if (!$match['validate']($result[$match['name']])) {
+                if (!$match['validate']($result[$match['name']], $this->getSelector()->getSourceKey())) {
                     $this->addLog('Skipping match because validation failed for '.$match['name'].': '.$result[$match['name']]);
 
                     return false;
diff --git a/src/Laurentvw/Scrapher/Scrapher.php b/src/Laurentvw/Scrapher/Scrapher.php
index d25b90c..43c13ee 100644
--- a/src/Laurentvw/Scrapher/Scrapher.php
+++ b/src/Laurentvw/Scrapher/Scrapher.php
@@ -84,7 +84,7 @@ public function __construct($contents = null)
     public function addUrl($url)
     {
         $page = new Page($url);
-        $this->addContent($page->getHTML());
+        $this->addContent($page->getHTML(), $url);
 
         return $this;
     }
@@ -109,12 +109,16 @@ public function addUrls(array $urls)
      * Add content to scrape.
      *
      * @param string $content
-     *
+     * @param null $key
      * @return Scrapher
      */
-    public function addContent($content)
+    public function addContent($content, $key = null)
     {
-        $this->contents[] = $content;
+        if (!is_null($key)) {
+            $this->contents[$key] = $content;
+        } else {
+            $this->contents[] = $content;
+        }
 
         return $this;
     }
@@ -305,8 +309,8 @@ protected function scrape()
 
         $results = array();
 
-        foreach ($this->contents as $content) {
-            $results = array_merge($results, $this->getMatcher()->getMatches($content));
+        foreach ($this->contents as $id => $content) {
+            $results = array_merge($results, $this->getMatcher()->getMatches($content, $id));
         }
 
         if ($results) {
diff --git a/src/Laurentvw/Scrapher/Selectors/RegexSelector.php b/src/Laurentvw/Scrapher/Selectors/RegexSelector.php
index 1bb93a7..58f9c0a 100644
--- a/src/Laurentvw/Scrapher/Selectors/RegexSelector.php
+++ b/src/Laurentvw/Scrapher/Selectors/RegexSelector.php
@@ -14,6 +14,10 @@ public function getMatches()
 
         foreach ($matchLines as $i => $matchLine) {
             foreach ($this->getConfig() as $config) {
+                if ($config['id'] == 0) {
+                    $matches[$i][$config['name']] = $this->getSourceKey();
+                    continue;
+                }
                 if (!isset($matchLine[$config['id']])) {
                     throw new MatchIdNotFoundException($config['id']);
                 }
diff --git a/src/Laurentvw/Scrapher/Selectors/Selector.php b/src/Laurentvw/Scrapher/Selectors/Selector.php
index 342c0a4..ac8e987 100644
--- a/src/Laurentvw/Scrapher/Selectors/Selector.php
+++ b/src/Laurentvw/Scrapher/Selectors/Selector.php
@@ -4,7 +4,7 @@
 
 abstract class Selector
 {
-    private $content, $expression, $config;
+    private $content, $sourceKey, $expression, $config;
 
     public function __construct($expression, $config)
     {
@@ -22,6 +22,16 @@ public function getContent()
         return $this->content;
     }
 
+    public function setSourceKey($key)
+    {
+        $this->sourceKey = $key;
+    }
+
+    public function getSourceKey()
+    {
+        return $this->sourceKey;
+    }
+
     public function setConfig($config)
     {
         $this->config = $config;