Thanks sebastian.s! Yes, "fork-joint" is one way. However, as I understand the "fork-joint" which the tasks need to be defined in the process definition. But our requirment is that the number of tasks only know during the runtime. We cannot define the fix number of task in the "fork-joint" in the process definition. We need to inject the tasks into the "fork-joint" in runtime, can the jBPM 4 do that? View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4260781#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...