diff --git a/user_guide/changelog.html b/user_guide/changelog.html
index 648c922..4129046 100644
--- a/user_guide/changelog.html
+++ b/user_guide/changelog.html
@@ -68,6 +68,8 @@
 		<ul>
 			<li>Added <kbd>$config['cookie_secure']</kbd> to the config file to allow requiring a secure (HTTPS) in order to set cookies.</li>
 			<li class="reactor">Added the constant <kbd>CI_CORE</kbd> to help differentiate between Core: TRUE and Reactor: FALSE.</li>
+			<li class="reactor">Added an <kbd>ENVIRONMENT</kbd> constant in index.php, which affects PHP error reporting settings, and optionally, 
+                which configuration files are loaded (see below). Read more on the <a href="general/environments.html">Handling Environments</a> page.</li>
 			<li class="reactor">Added support for <a href="libraries/config.html#environments">environment-specific</a> configuration files.</li>
 		</ul>
 	</li>