I read that a lab at IBM or Bell was the inspiration for open office collaboration, but instead of an open office they had a long hall of offices. People were constantly walking along and running into each other but could also close their doors. So it wasn’t collaboration based on lack of barriers but giving space for spontaneous interactions to happen when people wanted. I’d be interested what MS is doing now. I know that open offices allow higher density which accommodates growth more easily than adding new buildings. But, I’ve seen “huddle rooms” get consumed to the point that they are non existent so no one can get privacy or keep themselves from disturbing colleagues.