Jim, Alexander had a thread going about this on zope@zope.org and it looks like Michel has answered to the effect that a persistant object like a property is thread safe. I just discovered that the reason it wasn't adding to the counter was possibly bug related and due to a <!--#call "Catalog.manage_Catalogobject()"--> call. It seemed to not allow the DTML page to process, but didn't give me a traceback, it just processed the rest of the page. It works now that I use and external method for Cataloging. I'm going to use the counter because it's not complex, and I just need a way of knowing that there won't be an already exists error when creating objects. I want object id's not to be the responsibility of the user. Autocreation of the id's seems easiest this way. Although globally unique identifiers have more power when doing the kind of Cataloging, referenceing stuff I'm doing. How hard would it be to implement? All my best (sorry for the long reply) Jason Spisak webmaster@mtear.com