I tried to figure out whether these fit small or large.  I read some previous reviews.  I went to a store and tried on other similar shoes made by Ryka.  They had plenty of room.  These are almost too small for my usual size.  I substituted a pair of inserts with better heel shock absorption, which also slightly affected the fit.  Decent support for Zumba.  If I ordered again, I think I'd order a half-size larger.