Hi Ion, have you thought about instantiating two different interfaces for constant and non-constant time size() lists respectively? Instead of instantiating one interface that has differing complexity guarantees and is restricted by the lowest common denominator of what is possible with constant-time size(). Non-constant time size() lists would allow to implement higher level functionality as static member functions or as non-member functions, and some functionality like splicing needs no additional list& parameter. If I had such a list I could make my functions work on iterator ranges without the need to pass the list object along. So what I need is access to the nodes so that I can call circular_list_algorithms directly on these. I don't see an easy way to achieve that goal right now. As far as I can tell I need to use the undocumented list_iterator::pointed_node() function - which is okay, I'm only hesitant because it is undocumented. I'm willing to change my code if that interface ever changes though. Kevin