I am 6'2" tall and weigh 180 lbs and I ordered the medium as I read here that this jacket ran big, and I'm glad I did. Plenty of room in the arms for those with bigger arms, a little tight on the back but really easy to move in, very light and yet warm, I'm very pleased with what they call the "slim fit" which is just regular fit for me, it's just so hard to find a jacket that is not made for men with huge bellys in the U.S.