I cannot seem to get these sandals right. I ordered a 6.5 first, which were a bit tight and my toes were at the very end, but somehow the back strap kept falling off. I decided to order a larger size so I had some room and did not stretch the straps out too much. The 7.5 is much comfier, but the back strap will still not stay on my heal. I bought these after reading the reviews of people walking around long distances without their feet hurting. I can't imagine they will be good for walking long distances, because it is very annoying to keep adjusting them. They do not stay on well without that back strap.