I would disagree with @Jolek, if you're looking for a full range of movement a small may be better. See this post I made late last year: http://www.styleforum.net/t/512884/arcteryx-veilance-is-field-jacket-any-clue-on-sizing/0_100#post_8201670 I am 5'8, just under 160 pounds, and wear a medium. I tried on a small and it looked better standing still while in front of a mirror, but the shoulders felt tight as soon as I swung my arms. Very happy with my size M.
6/15/16 at 7:10pm