Sure, you can use /ksession.addEventListener( listener )/ to add your listeners. You'll have to implement the /AgendaEventListener/ interface: in particular, the /beforeActivationFired/ and /afterActivationFired/ handlers. If needed, the /WorkingMemoryEventListener/ will let you monitor object insertions and retractions. You can also see section 4.3.5 in the Drools Expert User Guide for more details. Davide -- View this message in context: http://drools.46999.n3.nabble.com/How-to-monitor-drools-execution-time-tp... Sent from the Drools: User forum mailing list archive at Nabble.com.