Hi thanks for your message... but the below is what given in the manual... ================= The Rule Base also holds references to any stateful session that it has spawned, so that if rules are changing (or being added/removed etc. for long running sessions), they can be updated with the latest rules (without necessarily having to restart the session). You can specify not to maintain a reference, but only do so if you know the Rule Base will not be updated. References are not stored for stateless sessions. ============ Wat does this session means... is that adding facts to the working... that is what it is explained in 2.5.5 and 2.5.6 section in the manual... ===================== Please help thanks in advance -- View this message in context: http://www.nabble.com/StateFullSession---StatelessSession-tp16940355p1694... Sent from the drools - user mailing list archive at Nabble.com.