This might help but will need a bit of hacking to work outside our environment: http://www.mems-exchange.org/software/files/tmp/zodb_referers.py Anton and I have found it very useful when trying to track down references. To use: $ ./zodb_referers.py -c index.pkl That will create the index and then start prompting for OIDs. To reuse the index: $ ./zodb_referers.py index.pkl HTH, Neil