The fitting guide list waist and chest size. I think if you bought it to fit over the largest area (waist or chest) it would fit ok. You probably have to order and try it, or find a local store and try. I have a few down vest and this sweater/shirt is much thinner (good) , and very light, and not bulky at all. Should be excellent under layer that doesn't bulk me up and restrict arm movement. Good stuff.How would it fit a person whose physique was not stylishly tapered toward the waist?