These shoes are VERY comfortable but as others stated, run very large - at least 1 full size. Had to exchange for the next size down. The measurement chart from ECCO is accurate so best to actually check the overall length of your foot from longest toe to heel to select the proper size. Width wise, these are well suited to a true M. Narrow feet will swim in the toe bed and wide feet might experience an uncomfortable rubbing of the straps. I have a strong high instep and the arch support is minimal but tolerable Other than the size issue, the leather is glove soft and the sandal feels as though walking on a cloud. Perfect for the beach lifestyle going from long boardwalk strolls to casual dining outings. Will purchase in other colors.