I was a little confused about the sizing with these Birkenstocks as they are listed on Amazon as N or M and the size chart doesn't explain exactly what that means. Ordinarily, I would never be able to wear a Med or Reg size shoe, since I have a wide foot (EE) I ordered M and they fit perfectly and are so comfortable! They do take some breaking in though as previous reviews stated, but I was so excited to have them, I wore them to work the first day and stood on my feet for 5 hours straight. No surprise they hurt my feet, my knees, and my back. My own fault. I had a tiny squeek in the left shoe the first day, but I loosened the straps and that stopped. They're feminine and I love the way they look with jeans or slacks.