Drools uses predicates, so your rules are like "When for an Application, There is a Property such that...{condition condition condition}, Then do something with the application and property" So you insert all your Applications and Properties into working memory... Then you'd have, excuse my unchecked guess at how it would be done: rule "show all properties" when application: Application(status == VALID) property : Property(id == 3) then System.out.println(application.getName() + "matched property 3") end -- View this message in context: http://n3.nabble.com/newbie-hard-time-understanding-how-to-use-the-rules-... Sent from the Drools - User mailing list archive at Nabble.com.