diff --git a/src/QueryExpressionFilter.php b/src/QueryExpressionFilter.php
index b848b4d..a0d63f6 100644
--- a/src/QueryExpressionFilter.php
+++ b/src/QueryExpressionFilter.php
@@ -7,11 +7,12 @@
 class QueryExpressionFilter implements Filter
 {
     private $queryExpression;
-    private $selectorSeparator = '.';
+    private $selectorSeparator;
 
-    public function __construct($queryExpression)
+    public function __construct($queryExpression, $selectorSeparator = '.')
     {
         $this->queryExpression = $queryExpression;
+        $this->selectorSeparator = $selectorSeparator;
     }
 
     public function doesMatch($data)
@@ -133,8 +134,18 @@ private function matchValue($data, $column, $expectation)
 
     private function fetchValue($data, $column)
     {
-        // TODO: dotted notation
-        return isset($data[$column]) ? $data[$column] : null;
+        $path = explode($this->selectorSeparator, $column);
+
+        $current = $data;
+        foreach ($path as $field) {
+            if (is_array($current) && isset($current[$field])) {
+                $current = $current[$field];
+            } else {
+                return null;
+            }
+        }
+
+        return $current;
     }
 
     private function isObject($value)
diff --git a/tests/QueryExpressionFilterTest.php b/tests/QueryExpressionFilterTest.php
index 46ba0d9..786f2e8 100644
--- a/tests/QueryExpressionFilterTest.php
+++ b/tests/QueryExpressionFilterTest.php
@@ -18,6 +18,22 @@ public function testAttributeValue()
             'id' => 200
         )));
 
+        $filterNested = new QueryExpressionFilter(array(
+            'nested.attribute' => 250
+        ));
+
+        $this->assertTrue($filterNested->doesMatch(array(
+            'nested' => array(
+                'attribute' => 250
+            )
+        )));
+
+        $this->assertFalse($filterNested->doesMatch(array(
+            'nested' => array(
+                'attribute' => 300
+            )
+        )));
+
         return $filter;
     }
 
@@ -363,4 +379,68 @@ public function testInvalidOr()
 
         $filter->doesMatch(array('id' => 100));
     }
+
+    /**
+     * @dataProvider dpFetchValue
+     */
+    public function testFetchValue($data, $fetch, $expected, $separator = '.')
+    {
+        $filter = new QueryExpressionFilter(array(), $separator);
+        $method = new \ReflectionMethod($filter, 'fetchValue');
+        $method->setAccessible(true);
+
+        $this->assertEquals(
+            $expected,
+            $method->invoke($filter, $data, $fetch)
+        );
+    }
+
+    public function dpFetchValue()
+    {
+        return array(
+            array(
+                array('id' => 1),
+                'id',
+                1
+            ),
+            array(
+                array(
+                    'org' => array(
+                        'peoples' => array(
+                            'john' => array(
+                                'weight' => 80
+                            )
+                        )
+                    )
+                ),
+                'org.peoples.john',
+                array(
+                    'weight' => 80
+                )
+            ),
+            array(
+                array(
+                    'org' => array(
+                        'peoples' => array(
+                            'john' => array(
+                                'weight' => 80
+                            )
+                        ),
+                        'computers' => array(
+                            'pc' => 'Intel',
+                            'macbook' => 'Macbook Pro'
+                        )
+                    )
+                ),
+                'org:computers:pc',
+                'Intel',
+                ':'
+            ),
+            array(
+                array('id' => 1),
+                'unexpected',
+                null
+            ),
+        );
+    }
 }