I was confused about what size to order in this shoe. I'm a size 10, wear a 41 in Euro sizing and yet they say a 41 is a 9.5 on these (I thought it was a 10). Reviewers said they run big, though, so I went with the 9.5/41. They are about what I would expect a true 10 to be, so I was right to stick to my normal Euro size. Vans and Converse run big and they are similar/unisex shoes, so perhaps they mark these a smaller size in U.S. sizing to keep with the expectation we have of Vans and Converse-- to size down. My feet are very low volume (skinny), though, and I'd planned to wear these without socks or with thin, no-show socks. They fit a little too loose for that for me (feet feel like they are swimming in them/heel slips) and I'm certain sizing down would only make them hit up against my toes too much. I have similar issues with unisex American styles. If you have normal or larger feet, you will probably love these. Mine are just too darn thin. These are much more comfortable than their American counterparts, in my opinion.