Groups is a Zope product that adds Group support to Zope. Groups should work without Silva, but this independent support is very raw at the moment (no user interface).

Note that the Groups product makes use of a rather dirty technique called monkey patching to add groups support to the Zope core. This may conflict with other products which try to do the same. If this turns out to be the case, it is safe to just remove the Groups directory from your Products directory and restarting Zope.

Note that Groups has only been tested with Zope 2.5.1.