I ordered a large one. I usually wear American Large (L) shirts, have a slim build and very broad, straight shoulders. This t-shirt has creases under the armpits, but everything else about it is perfect. The material is a smooth, silky antiperspirant fabric and the t-shirt has a slim fit. I really don't think the XL will make things any better because I don't need it to be bigger in the stomach or bigger in the upper body. I'll probably cut off the sleeves.