Hi, The Expert documentation says " a rule may fire once or several times", but I don't understand why a rule sould fire several times if the objects state does not change? I have an example of a Customer object inserted in the Working Memory, with 2 rules that should fire, but the last rule fires twice. Can someone explain? rule "isAdult" when k : Customer( age(date)>=18, adult==false ); then modify( k ) { setAdult(true) }; System.out.println( "Drools "+drools.getRule().getName()+": "+ k.getAdult() ); end rule "WM" when k : Customer( ) ; then System.out.println( "Drools "+drools.getRule().getName()+": " +k.getName()); end ... Customer bert = new Customer (); bert.setName("Bert"); bert.setDate(30); ksession.insert(bert); ksession.fireAllRules(); ... Output: Drools WM: Bert Drools isAdult: true Drools WM: Bert Br, Els Destickere -- View this message in context: http://drools.46999.n3.nabble.com/rule-fires-several-times-tp3466250p3466... Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users