---
title: Upgrade Notes
description: Important changes to consider when upgrading to Istio 1.5.
weight: 20
---

This page describes changes you need to be aware of when upgrading from
Istio 1.4 to 1.5.  Here, we detail cases where we intentionally broke backwards
compatibility.  We also mention cases where backwards compatibility was
preserved but new behavior was introduced that would be surprising to someone
familiar with the use and operation of Istio 1.4.

TBD
