diff --git a/CHANGELOG.md b/CHANGELOG.md
index 09dc393..5f965dc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,19 +22,21 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Fixed
 
-- Nothing.
+- [#21](https://github.com/zendframework/zend-dom/pull/21) fixes an issue with
+  matching against nested attribute selectors (e.g., `div[class="foo"] div
+  [class="bar"]`), ensuring such syntax will transform to expected XPath.
 
 ## 2.7.0 - 2018-03-27
 
 ### Added
 
-- [#20](https://github.com/zendframework/zend-dom/pull/4) adds support for
+- [#20](https://github.com/zendframework/zend-dom/pull/20) adds support for
   attribute selectors that contain spaces, such as `input[value="Marty McFly"]`.
   Previously, spaces within the selector value would result in a query per
   space-separated word; they now, correctly, result in a single query for the
   exact value.
 
-- [#19](https://github.com/zendframework/zend-dom/pull/4) adds support for PHP
+- [#19](https://github.com/zendframework/zend-dom/pull/19) adds support for PHP
   versions 7.1 and 7.2.
 
 - Adds documentation and publishes it to https://docs.zendframework.com/zend-dom/
@@ -45,12 +47,12 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Removed
 
-- [#13](https://github.com/zendframework/zend-dom/pull/4) and
-  [#19](https://github.com/zendframework/zend-dom/pull/4) remove support for PHP
+- [#13](https://github.com/zendframework/zend-dom/pull/13) and
+  [#19](https://github.com/zendframework/zend-dom/pull/19) remove support for PHP
   versions prior to 5.6.
 
-- [#13](https://github.com/zendframework/zend-dom/pull/4) and
-  [#19](https://github.com/zendframework/zend-dom/pull/4) remove support for HHVM.
+- [#13](https://github.com/zendframework/zend-dom/pull/13) and
+  [#19](https://github.com/zendframework/zend-dom/pull/19) remove support for HHVM.
 
 ### Fixed
 
@@ -60,7 +62,7 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Added
 
-- [#2](https://github.com/zendframework/zend-dom/pull/4) ads context node
+- [#2](https://github.com/zendframework/zend-dom/pull/2) adds context node
   support for DOMXPath->query that supports querying in the context of a
   specific node.
 
diff --git a/src/Document/Query.php b/src/Document/Query.php
index 7b40a8e..7b2fc8c 100644
--- a/src/Document/Query.php
+++ b/src/Document/Query.php
@@ -88,9 +88,9 @@ public static function cssToXpath($path)
 
         // Arbitrary attribute value contains whitespace
         $path = preg_replace_callback(
-            '/\[\S+["\'](.+)["\']\]/',
+            '/\[\S+?([\'"])((?:(?!\1)[^\\\]|\\.)*)\1\]/',
             function ($matches) {
-                return str_replace($matches[1], preg_replace('/\s+/', '\s', $matches[1]), $matches[0]);
+                return str_replace($matches[2], preg_replace('/\s+/', '\s', $matches[2]), $matches[0]);
             },
             $path
         );
@@ -147,29 +147,29 @@ protected static function _tokenize($expression)
 
         // arbitrary attribute strict equality
         $expression = preg_replace_callback(
-            '|\[@?([a-z0-9_-]+)=[\'"]([^\'"]+)[\'"]\]|i',
+            '/\[@?([a-z0-9_-]+)=([\'"])((?:(?!\2)[^\\\]|\\.)*)\2\]/i',
             function ($matches) {
-                return '[@' . strtolower($matches[1]) . "='" . $matches[2] . "']";
+                return sprintf("[@%s='%s']", strtolower($matches[1]), str_replace("'", "\\'", $matches[3]));
             },
             $expression
         );
 
         // arbitrary attribute contains full word
         $expression = preg_replace_callback(
-            '|\[([a-z0-9_-]+)~=[\'"]([^\'"]+)[\'"]\]|i',
+            '/\[([a-z0-9_-]+)~=([\'"])((?:(?!\2)[^\\\]|\\.)*)\2\]/i',
             function ($matches) {
                 return "[contains(concat(' ', normalize-space(@" . strtolower($matches[1]) . "), ' '), ' "
-                     . $matches[2] . " ')]";
+                     . $matches[3] . " ')]";
             },
             $expression
         );
 
         // arbitrary attribute contains specified content
         $expression = preg_replace_callback(
-            '|\[([a-z0-9_-]+)\*=[\'"]([^\'"]+)[\'"]\]|i',
+            '/\[([a-z0-9_-]+)\*=([\'"])((?:(?!\2)[^\\\]|\\.)*)\2\]/i',
             function ($matches) {
                 return "[contains(@" . strtolower($matches[1]) . ", '"
-                     . $matches[2] . "')]";
+                     . $matches[3] . "')]";
             },
             $expression
         );
diff --git a/test/Document/QueryTest.php b/test/Document/QueryTest.php
index afcc7ca..7683bf4 100644
--- a/test/Document/QueryTest.php
+++ b/test/Document/QueryTest.php
@@ -172,4 +172,34 @@ public function testCanTransformWithAttributeAndDot()
         $test = Query::cssToXpath('a[@href="http://example.com"]');
         $this->assertEquals("//a[@href='http://example.com']", $test);
     }
+
+    public function nestedAttributeSelectors()
+    {
+        return [
+            'with-double-quotes' => [
+                'select[name="foo"] option[selected="selected"]',
+                "//select[@name='foo']//option[@selected='selected']",
+            ],
+            'with-single-quotes' => [
+                "select[name='foo'] option[selected='selected']",
+                "//select[@name='foo']//option[@selected='selected']",
+            ],
+            'double-quotes-containing-single-quotes' => [
+                "select[name=\"f'oo\"] option[selected=\"sel'ected\"]",
+                "//select[@name='f\'oo']//option[@selected='sel\'ected']",
+            ],
+            'single-quotes-containing-double-quotes' => [
+                "select[name='f\"oo'] option[selected='sel\"ected']",
+                "//select[@name='f\"oo']//option[@selected='sel\"ected']",
+            ],
+        ];
+    }
+
+    /**
+     * @dataProvider nestedAttributeSelectors
+     */
+    public function testTransformNestedAttributeSelectors($selector, $expectedXpath)
+    {
+        $this->assertEquals($expectedXpath, Query::cssToXpath($selector));
+    }
 }