diff --git a/modules/image/image.api.php b/modules/image/image.api.php
index 8115116..c317997 100644
--- a/modules/image/image.api.php
+++ b/modules/image/image.api.php
@@ -195,6 +195,35 @@ function hook_image_default_styles() {
   return $styles;
 }
 
+/**
+ * Modify the URI's TokenQuery generated for image styles.
+ *
+ * This hook allows modules to modify, add, or remove the TokenQuery associated
+ * to image styles URIs. The hook is invoked after the creation of the URI for
+ * an image style, thus the URI can not be altered here.
+ *
+ * @param array $token_query
+ *   The list of tokens defined for the given image style URI.
+ * @param array $context
+ *   The hook invocation context, an associative array with the following keys:
+ *    - uri: the URI of the image style
+ *    - style_name: the image style
+ *    - path: the path that originated the current URI
+ */
+function hook_image_style_uri_token_query_alter(&$token_query, $context) {
+  // Example1: Adding a new TokenQuery if the image_style's name matches our check.
+  if ('my-style-name' == $context['style_name']) {
+    // Let the original URI get the "?my-token=my-value" query token appended.
+    $token_query['my-token'] = 'my-value';
+  }
+
+  // Example2: Clearing the TokenQuery if the image_style's path schema is "private://".
+  $schema = file_uri_scheme($context['path']);
+  if ('private' == $schema) {
+    $token_query = array();
+  }
+}
+
  /**
   * @} End of "addtogroup hooks".
   */
diff --git a/modules/image/image.module b/modules/image/image.module
index 526330c..13a9754 100644
--- a/modules/image/image.module
+++ b/modules/image/image.module
@@ -1049,6 +1049,11 @@ function image_style_url($style_name, $path) {
   }
 
   $file_url = file_create_url($uri);
+
+  // Allow modules to alter the $token_query for the given style.
+  $context = array('uri' => $uri, 'style_name' => $style_name, 'path' => $path);
+  drupal_alter('image_style_uri_token_query', $token_query, $context);
+
   // Append the query string with the token, if necessary.
   if ($token_query) {
     $file_url .= (strpos($file_url, '?') !== FALSE ? '&' : '?') . drupal_http_build_query($token_query);