"kukeltje" wrote : how do you mean stateless? Is that the same as no persistence to you? 95% of current jBPM usage is with persistance, Can you point me to the wiki page and tell me what you think this statefull means? The wiki page is here: http://www.jboss.org/community/docs/DOC-12855 My understanding for current jBPM is, the state of a process instance (during the execution, where the token points) is persistent in the database. Thus suppose I have a service to call jBPM to execute a process, I can make this service stateless because this service does not need to carry the state of current process (the state is in the persistence). This service does not need to wait for jBPM and keep its state. It simply call jBPM, signal the token and return. Next time when the service access this process instance again, it will know the state from the persistence. Otherwise, I have to make my service stateful which from my perspective may affect scalability of my system. I am not sure if this is what jBPM team means by stateless process instance or statefull process instance. I am just concerned whether or not I can still keep my service stateless. BTW, in existing code base, jbpm enterprise has a stateless EJB implemenation. That is why I think I can have a stateless service in my system to interact with jBPM. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4188955#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...