Hi! Currently the OrderSupport API always orders sub-objects relative to the complete list of sub-objects. This causes problems if some hidden sub-objects are not shown. From an UI point of view, moving sub-objects should always be relative to the visible subset of sub-objects. I'd like to add a new optional argument to moveObjectsByDelta (and the derived methods moveObjectsUp, moveObjectsDown, moveObjectsToTop, moveObjectsToBottom): subset_ids This would be 100% backwards compatible and would allow to specify the visible subset of sub-objects. def moveObjectsByDelta(ids, delta, subset_ids=None): If subset_ids is specified, delta will be interpreted relative to that subset. If there are no objections I'll soon check in the necessary changes to Zope-2_7-branch and HEAD. Cheers, Yuppie