diff --git a/CHANGELOG.md b/CHANGELOG.md
index f7270b332..e98a82ce5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,6 @@
 # Change Log
 
-## Unreleased
+## [v3.5.2] (2024-09-16)
 - FlattenedNodesObserver.getFlattenedNodes was accidentally quadratic if given a non-slot node. Found by @mvanbem-goog.
 
 ## [v3.5.1](https://github.com/Polymer/polymer/tree/v3.5.1) (2022-06-03)
diff --git a/package.json b/package.json
index 5fb8aa5cf..1ed5a094e 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@polymer/polymer",
-  "version": "3.5.1",
+  "version": "3.5.2",
   "description": "The Polymer library makes it easy to create your own web components. Give your element some markup and properties, and then use it on a site. Polymer provides features like dynamic templates and data binding to reduce the amount of boilerplate you need to write",
   "main": "polymer-element.js",
   "module": "polymer-element.js",