Hello, I'm implementing a simple event processing application, and I'm getting unexpected results. I use the time operator "this after" and I declare one of my events with an "@expires" property. I want to detect an event with a certain attribute (let's call it "main event"), and when this event arrives I want to initiate a timer so that I collect all the events that arrive within the next 10 seconds, regardless of their attributes. A second timer should never be initiated until the first one ends. In order to implement this scenario I used an auxiliary event, named "Context", that is inserted in the working memory when the "main event" is detected, and expires after 10 seconds. So I have two rules: the first one detects the "main event" (when there's no Context in the working memory) and inserts a Context event. The second rule fires when there's a Context event, and lists all the other events that arrive within the next 10 seconds. The rules are bellow: rule "Detect Main Event" activation-group "A" lock-on-active true salience 1 when $event : Notif( specificProblem == "New ONT" || specificProblem == "ONT Is Inactive" ) && not Context() then System.out.println("Context Created by "+$event.getSpecificProblem()+" "+$event.id); insert( new Context($event) ); end rule "Collect Events in a 10 second window" activation-group "A" lock-on-active true salience 2 when $context : Context() $list10s : List() from collect ( Notif( this after [0s,10s] $context )) then Notif notifContext = $context.getNotif(); System.out.println("context: "+notifContext.getSpecificProblem()+" "+notifContext.id); Helper.printList($list10s); end The output I get is the following: /0s: New ONT 1/ Context Created by New ONT 1 /2s: ONT is inactive 1/ context: New ONT 1 -List: --ONT Is Inactive1 --- /4s: ONT is inactive 2/ context: New ONT 1 -List: --ONT Is Inactive1 --ONT Is Inactive2 --- /7s: New ONT 2/ context: New ONT 1 -List: --ONT Is Inactive1 --ONT Is Inactive2 --New ONT2 --- */22s: New ONT 3/ context: New ONT 1 Empty list /27s: New ONT 4/ Context Created by New ONT 4* The lines in italic are the events I receive, and the respective time instance, in seconds. The lines in bold are the unexpected results. When I receive event "New ONT 3", the "Context" should have expired by then and it should create a new one. What could be causing this? It seems to work properly until I receive that event. Any help would be greatly appreciated, as I've tried several modifications and none seem to work. Thanks in advance, Diana -- View this message in context: http://drools.46999.n3.nabble.com/Event-processing-Drools-Fusion-problem-... Sent from the Drools: User forum mailing list archive at Nabble.com.