I ordered this shoe to do water aerobics.  I am normally a 9 or 9.5 so I ordered a 9.  They were very large and would have slipped off in the water.  I liked the comfort so much that I took a chance on an 8.  They are perfect for me in the water.  I have a high arch, and these have a high arch for a sandal.  They are super comfortable and dry very quickly.  If you want these for walking in or around water and want a more snug fit, these are perfect.  I'm ordering another pair for when these wear out.  I like not having my foot confined as well as having excellent support.