I'm 5'9", 165 and the small was ideal for me. The jacket does seem to run big, as it demands layers. I loved the zipper to the side of the face, just a small detail, but great functionality. The hood is rather large. If you don't plan on wearing a helmet at any point in your use of this item you may look into other Gore jackets, because the hood is large. For the price you want to make sure its going to be well used. Its not a problem if you cinch down the cords on the hood real tight. Otherwise you'll feel like a parasailer when the wind catches you. Impressive design, Arcteryx didn't forget what the use of this jacket was. It could use a larger interior pocket for a pair of skins.