If you are really interested in staircase (some sad people like me are :) ) then this is a great book. It has choosen some of the best contemporary staircase from around the world. The only downsides are there very few words to discribe things like materials, design issues and structure. If you want to see lots of pretty pictures of stairs it's great, just don't expect it to help with any architecture courses ect.
Also it has missed out some of the greatest staircase designs, posibly because they are to classical.