I knew from previous experience with Columbia hikers that they tend to run small.  I normally wear a size 10M in almost every style or brand of shoe, but the last time I bought Columbia hikers, the size 10 was much too small, so I ordered up to an 11M.  This time, I decided to go with a 10.5M, and they just barely fit with thin, nylon stockings.  I really like the way they look, but wish they were more comfortable.  The more I wear them, the more comfortable they get, and I am happy with the shoe....but I should have ordered them in an 11.  I would recommend these shoes, as long as you order in the next size up.