When I first saw this shoe, I figured I'd never be able to walk in it with a heel that high but it was suprisingly comfortable.  The shoe is well engineered enough so that the ankle strap is comfortable and has plenty of adjustability, and the other straps hug the foot nicely.  I wear a 7 to 7 1/2 in dress shoes and was able to take a 7 in this.  I wouldn't recommend sizing up.  I'm 60 years old and I don't feel the style is too "young" for me.