Hi, I just released an enhanced version of Scott Raymond''s assert_valid_markup plugin that I have been using. Basically it allows you to validate (X)HTML or CSS files generated by application during testing. I have described the basics of it at; http://www.realityforge.org/articles/2006/03/15/rails-plugin-to-validate-x-html-and-css or you can grab it from subversion at http://www.realityforge.org/svn/public/code/assert-valid-asset/trunk/ -- Cheers, Peter Donald