JSF validation is great for ensuring an isolated field is valid (e.g. Postcode, Bank Account No, National Insurance No). I haven't used it to do 'contextual validation'. I don't think you can use the Hibernate Validator in the JSF validation phase in such a way - @AssertTrue and @AssertFalse might be useful but as the JSF validation phase is before the model update phase the model won't have been updated with new values. I'm not sure what the best solution is, I would suggest in the action method BUT that would require you to rollback parts of the entity if invalid values are entered. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3959505#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...