diff --git a/railties/guides/source/configuring.textile b/railties/guides/source/configuring.textile
index ab9dd220bdca34f5496516596d676c6b07ef5546..fcf7ba0ae55aeb088ab8786dce7f4d10d120772e 100644
--- a/railties/guides/source/configuring.textile
+++ b/railties/guides/source/configuring.textile
@@ -230,6 +230,8 @@ h4. Configuring Action Controller
 
 * +config.action_controller.page_cache_extension+ configures the extension used for cached pages saved to +page_cache_directory+. Defaults to +.html+
 
+* +config.action_controller.perform_caching+ configures whether the application should perform caching or not. Set to _false_ in development mode, _true_ in production.
+
 * +config.action_controller.default_charset+ specifies the default character set for all renders. The default is "utf-8".
 
 * +config.action_controller.logger+ accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then used to log information from Action Controller. Set to nil to disable logging.