Hi Roland, maybe you are right. For sure performance is a issue and there should be a lot of indices. I'm only evaluating jBPM for future use a I thought this would be more general than business key. I have not found a process yet where you need to search for a task with more than one criteria (on one page tasks will be listed with one criteria, on another with another criteria). So from this perspective business key is ok. But I have found this use case: You start business process on page where business object BO1 is present, business object creates another business object BO2 some tasks are present on the page where you edit BO1, some on the page where you edit BO2. Does it mean that I should store some kind of ssn and save the same in both objects? I thought that to search for tasks will make from this the same issue as if searching for business object. And this one (only fictive not form business) case where business key is not enough: Imagine "friend link" example. On the page of first user sees all requests he requested and he can cancel some of them -> key should be friend. User2 sees all the requests he can accept/reject -> key should be friend2 They can't have the same key. So solution for this is to have business key in TaskInstance not in ProcessInstance. And this will be the solution for first case as well and I can left out ssn form business object:) I think that it is better to refence object form process and not vice versa. Now we use this solution and I call it business object as "task owner" and the id of business task is stored in task variable. It is not the same as assigning task to user because authorization is there as well so it is assigning task to combination of showed business object and logged user. What do you think about this? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4179788#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...