Hi Steve, Since you found the external methods arguments thing interesting, here's another challenge for you... ;-) (it's actually from the same nav_tree method) I was trying to use 'if o in REQUEST.PARENTS' to expand branches on the way to the currently displayed object and was running into trouble which lead me to try out the following code: `REQUEST.PARENTS[0]`+`o`+`o==REQUEST.PARENTS[0]`+`o is REQUEST.PARENTS[0]` Now, this renders the following in the case where the branch _should_ expand: <Folder instance at 88cbb30><Folder instance at 88cbb30>00 What I don't understand is how two objects, apparently at the same memory location, return false from both 'object1==object2' and 'object1 is object2'. Again, any ideas? cheers, Chris The only vaguely related thing I can think of is that this is happening 'cos I'm working in a version and the folder object has been changed and REQUEST.PARENTS contains the unchanged version while o contains the changed version. If this is causing it, it's a bug ;-)