Hi, I am new to EJB3 as well, and struggling with the same issue. From what I can tell it is the way the system is designed. You many want to start by reading this: http://www.hibernate.org/43.html So my take on it is that you may not want the client modifying the collections on your POJOs outside the scope of a transaction. I have a post on the EJB3 forum here that ask the same question, except my example is a tree that supports recursion. My issue was that I wanted to be able to modify the tree nodes directly. See: http://www.jboss.org/index.html?module=bb&op=viewtopic&t=87956 But if you think about it in a more transaction oriented light, it doesn't make sense to modify the entity directly. Instead you would want the server controlling the whole transaction. For example moving tree nodes from one part of the tree to another is something you really want backed by a transaction. No don't get me wrong, I am not thrilled about the design, but it sure seems to be better then EJB 2.0 -k View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3962645#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...