diff --git a/Data Structures/bstInvert.js b/Data Structures/bstInvert.js
new file mode 100644
index 0000000..25531b1
--- /dev/null
+++ b/Data Structures/bstInvert.js	
@@ -0,0 +1,27 @@
+// https://www.freecodecamp.org/learn/coding-interview-prep/data-structures/invert-a-binary-tree
+
+var displayTree = (tree) => console.log(JSON.stringify(tree, null, 2));
+function Node(value) {
+  this.value = value;
+  this.left = null;
+  this.right = null;
+}
+function BinarySearchTree() {
+  this.root = null;
+  // Only change code below this line
+  this.invert = () => {
+    if (this.root === null) {
+      return;
+    }
+    const stack = [this.root];
+    while (stack.length) {
+      const node = stack.pop();
+      const tmp = node.left;
+      node.left = node.right;
+      node.right = tmp;
+      if (node.left !== null) stack.push(node.left);
+      if (node.right !== null) stack.push(node.right);
+    }
+  };
+  // Only change code above this line
+}