Please see a previous message I sent to the list. You need a constraint that asymmetrically "orders" the events, so they can match one way but not the other: rule "Rules 1" when rt: Event( name1 : name == "SimpleEvent", id1 : id ) ru: Event( name2: name == name1, id2 : id > id1 ) then System.out.println("Rule matchs"); end Note the id>id1 in the above rule. []s Edson 2007/5/25, Nicolas Carlier <carlier.nicolas(a)gmail.com&gt;: -- Edson Tirelli Software Engineer - JBoss Rules Core Developer Office: +55 11 3529-6000 Mobile: +55 11 9287-5646 JBoss, a division of Red Hat @ www.jboss.com