diff --git a/README.md b/README.md
index ca75f9e..e68b781 100644
--- a/README.md
+++ b/README.md
@@ -165,6 +165,7 @@ var r = reqwest({
   * `error` A function called when the request fails.
   * `complete` A function called whether the request is a success or failure. Always called when complete.
   * `jsonpCallback` Specify the callback function name for a `JSONP` request. This value will be used instead of the random (but recommended) name automatically generated by reqwest.
+  * `processData` boolean (defaults to `true`), set to `false` if you want to skip reqwest's internal form serializer and process your data in a custom way. Eg: `data: JSON.stringify({ id: 1 })`
 
 ## Security