I wear a size 8 to 8 1/2 medium usually… I have a wider top of foot and a narrow heel which is a common problem… My hope for the shoe was that the elastic would hold it on better in the heel ... unfortunately the toebox is somewhat narrow and I probably could use a wide and eight however then the deal would slide off because it slides even in the eight medium… Not enough to return them though… So I will take them to a shoemaker to stretch out the  Front just a little… As far as style they are pretty cute I just don't care for the side with the little pieces of elastic which makes them look orthopedic… But because it's difficult to find semi flats that stay on I am going to keep them…  I don't know why Clark's makes flats that your heel slips out of all the time with these very narrow front portions of the shoe ...I've had this problem with other Clark shoes as well ..