Hi, There was talk a while back of re-doing BTree's in Zope so they were more efficient. Is that still going ahead? If I start using BTree folders now, will there be any nasties when the changes happen? Right, BTree folders wise, what I'm looking for is to have, in effect two Contents tabs for one BTree folder object, one showing all contained items of a particular meta_type (with the BTree Folder's interface to deal with lots of objects), and the other containing all other items in the folder (DTML Methods, Gifs, etc, with a normal folder's interface). What's the best way to do this? I was going going to subclass BTreeFolder, and overide the contents tab and provide an extra one, copying and hacking the DTML as appropriate to filter on meta_type. this strikes me as not very robust as I won't benefit from any improvements to either GUI that are made in the future. Is there perhaps a better way? Also, what's the difference between a 'Full' and a 'Basic' BTreeFolder, which one should I use? cheers, Chris