diff --git a/railties/guides/source/asset_pipeline.textile b/railties/guides/source/asset_pipeline.textile
index ba48a2196b8c6e2ad2dc9e0c0bda0e6788925c83..211b02b94b9775c38b9bcd15b0e679a58a6660cc 100644
--- a/railties/guides/source/asset_pipeline.textile
+++ b/railties/guides/source/asset_pipeline.textile
@@ -282,7 +282,7 @@ When debug mode is off Sprockets will concatenate and run the necessary preproce
 <script src='/assets/application.js'></script>
 </html>
 
-Assets are compiled and cached on the first request after the server is started. Sprockets sets a +must-validate+ Cache-Control HTTP header to reduce request overhead on subsequent requests -- on these the browser gets a 304 (not-modified) response.
+Assets are compiled and cached on the first request after the server is started. Sprockets sets a +must-revalidate+ Cache-Control HTTP header to reduce request overhead on subsequent requests -- on these the browser gets a 304 (not-modified) response.
 
 If any of the files in the manifest have changed between requests, the server responds with a new compiled file.