diff --git a/trees/find_inorder_successor.py b/trees/find_inorder_successor.py
new file mode 100644
index 0000000..db939cf
--- /dev/null
+++ b/trees/find_inorder_successor.py
@@ -0,0 +1,18 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
+
+def find_inorder_successor(root):
+
+    successor = None
+
+    while root:
+
+        if root.val <= p.val:
+            root = root.right
+        else:
+            successor = root
+            root = root.left
+
+    return successor