Hi, Shalabh helped me a lot further, he gave me an external method which helps me on the way, however I would like to know if it's possible to write this in a DTML-method. If this isn't possible, then why isn't this possible? Here is the external method (placed in the Methods view of a class) def manage_afterAdd(self,item,container): item.myparent=container.id return Is it possible to write this in DTML? No, not directly as far as I know. But refering to you first question: is there any reason why a <from the top of my head> <dtml-call "REQUEST.set('parent', container.id)"> <dtml-call "manage_changeProperties(REQUEST)"> after you created the instance would not work? I do this all the time. Or do I misunderstand your question? Rik