Johan, good to hear from ya ! as you mention in your point 2) can you give some concrete indication of what different dimensions your sticking into the actorId references ? or in other words: what kind of individual data items do you combine in the assignment String's ? secondly, our current plan is to make the difference between user-references and group-references more specific in the api. also we plan to have generic participations associated to tasks (and swimlanes). so you can associate users and groups as a participant to tasks or swimlanes and specify a participation like e.g. candidate, owner, viewer, client and so on. we have some constants defined, but participation is string based, so you can put your own participation if you like. would that help ? View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4210709#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...