I am 6'1" and the 56cm Fuji frame suits me well. The 58cm would also work, but I like my bikes compact, and do not look like a giant on this bike. I have looked at many BD Cross bikes and seem to have settled on a 56cm if I were to ever order one. I would think at 5'9"-ish that a 54cm or 56cm would work - it sucks being a tweener.