What if we change the engine to have parallel rendering ? Then the ordering would be totally random. It's a possibility open by the JSR-168 spec. Look at "PLT.5.2.4 Request Handling" anonymous wrote : The render requests may be executed sequentially or in parallel without any guaranteed order. Your app must not depend on the ordering of the windows. The only guarantee you have is that the action phase of the triggered portlet will be called before any rendering. Since all the render phases shouldn't have side-effect, it shouldn't be a problem. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4072862#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...