These shoes are to die for! Extraordinary design and  comfortable. I think, they run 1/2 size bigger. I buy 8.5 M because I have very small but disturbing bone on the left foot. Therefore, my left shoe is usually quite tight. This time my left is absolutely comfy and the right foot is just a little free. But it's OK, because the feet always a bit swell in summer. Awesome shoe! Strongly recommend.