Afaict, the pattern that you reference (Multiple Instances without synchronization) doesn't have anything to do with the original topic. Namely, how to synchronize between two concurrent paths of execution without joining them. Nevertheless, I do think that we can debate if our previous implementation of a milestone is really the milestone of vanderaalst. What was implemented previously is a wait state based on the state of another concurrent path of execution. If the other concurrent path of execution has passed a certain point, the token in this milestone node just continues. If not, the token will wait in this milestone until the other concurrent path of execution reaches that point. When that happens, the original token will continue to execute from the milestone. The milestone pattern is a bit different. There is says that the activity inside a node is executed depending on the state of a concurrent path of execution. So that doesn't involve wait states and recontinuation when the event is reached by the concurrent token. I believe that was the argument that someone pulled once... Anyways, it's easy to see that because we manage the complete runtime data structure as an object graph, that we can indeed inspect the complete runtime execution state of the complete process instance when the process executes. That gives us the ability to do 'whatever we want' :-) Have I rehabilitated myself ? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3982671#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...