diff --git a/menu_block.admin.inc b/menu_block.admin.inc
index 992a0cc..2236d1a 100644
--- a/menu_block.admin.inc
+++ b/menu_block.admin.inc
@@ -164,6 +164,7 @@ function menu_block_delete_submit($form, &$form_state) {
   variable_del("menu_block_{$delta}_level");
   variable_del("menu_block_{$delta}_follow");
   variable_del("menu_block_{$delta}_depth");
+  variable_del("menu_block_{$delta}_relative");
   variable_del("menu_block_{$delta}_expanded");
   variable_del("menu_block_{$delta}_sort");
 
@@ -412,6 +413,11 @@ function menu_block_configure_form($form, &$form_state) {
     ),
     '#description' => t('From the starting level, specify the maximum depth of the menu tree.'),
   );
+  $form['relative'] = array(
+    '#type' => 'checkbox',
+    '#title' => t('<strong>Allow depth</strong> to be relative to the starting level when following the active menu item.'),
+    '#default_value' => $config['relative'],
+  );
   $form['expanded'] = array(
     '#type' => 'checkbox',
     '#title' => t('<strong>Expand all children</strong> of this tree.'),
@@ -485,6 +491,7 @@ function _menu_block_block_save($delta = '', $edit = array()) {
       variable_set("menu_block_{$delta}_level", $edit['level']);
       variable_set("menu_block_{$delta}_follow", $edit['follow']);
       variable_set("menu_block_{$delta}_depth", $edit['depth']);
+      variable_set("menu_block_{$delta}_relative", $edit['relative']);
       variable_set("menu_block_{$delta}_expanded", $edit['expanded']);
       variable_set("menu_block_{$delta}_sort", $edit['sort']);
     }
diff --git a/menu_block.module b/menu_block.module
index f27659b..51e116b 100644
--- a/menu_block.module
+++ b/menu_block.module
@@ -215,6 +215,7 @@ function menu_block_get_config($delta = NULL) {
     'level'       => 1,
     'follow'      => 0,
     'depth'       => 0,
+    'relative'    => 0,
     'expanded'    => 0,
     'sort'        => 0,
   );
@@ -239,6 +240,7 @@ function menu_block_get_config($delta = NULL) {
     $config['level']       = variable_get("menu_block_{$delta}_level",       $config['level']);
     $config['follow']      = variable_get("menu_block_{$delta}_follow",      $config['follow']);
     $config['depth']       = variable_get("menu_block_{$delta}_depth",       $config['depth']);
+    $config['relative']    = variable_get("menu_block_{$delta}_relative",    $config['depth']);
     $config['expanded']    = variable_get("menu_block_{$delta}_expanded",    $config['expanded']);
     $config['sort']        = variable_get("menu_block_{$delta}_sort",        $config['sort']);
     $config['parent']      = variable_get("menu_block_{$delta}_parent",      $config['menu_name'] . ':' . $config['parent_mlid']);
@@ -260,7 +262,7 @@ function menu_tree_block_data(&$config) {
 
   if ($config['expanded'] || $config['parent_mlid']) {
     // Get the full, un-pruned tree.
-    if ($config['parent_mlid']) {
+    if ($config['parent_mlid'] || $config['relative']) {
       $tree = menu_tree_all_data($config['menu_name']);
     }
     else {