Overview I am trying to put an XML structure into a Zope product that mirrors the hierarchy. The dtd for the XML is roughly of the form <!ELEMENT nodes (node)*> <!ELEMENT node (node|leaf)*> <!ELEMENT leaf (object)*> <!ELEMENT object EMPTY> The 4 elements share several attributes and each has some unique attributes. So the intent is to group the common attributes in a couple of property pages and create an property page for each individual element. The desired ZClass representation is as follows: container (object manager) base () {to contain common property pages} nodes (object manager, base) node (object manager, base) leaf (object manager, base) object() I build the hierarchy, set permissions as follows and do the factory edit button trick container - add_nodes nodes - add_node node - add_node, add_twigs twigs - add_objects I instantiate a container, add a nodes object to the container, add a node to th nodes. At this point I can only add twigs though I think I should be able to add nodes. I thought I would look at the SubOjbects list however the only object that appears in the Subobjects list is nodes. Am I missing something here? I have tried countless permutations with and without the base class, deriving base from object manager etc... I think one of my prior iterations actually worked but without the base class concept though I seem unable to reproduce it now... Does anyone have any ideas? Thanks Bob