Bought this pair for a recent holiday trip to Hawaii.  I followed some earlier reviewers advice & bought them a size small.  Fit snug, but not uncomfortably so....stayed on my feet in the water & gave my feet good protection as I walked over the lava rock to get to the water.  Also the sole had a nice grip on that wet rock-so no slipping & looking like an idiot while everyone else on the beach is checking you out.  Would definitely recommend to a friend.