I wear small, but ordered 2 of these in medium. I've had on only one of them, and it is SOOOO tight. Cuts into armpits, and has so much "snap" it feels like a body shaper type garment. If you don't mind the feel of a girdle shirt, it's a great looking top. Recommend ordering 2 sizes larger than you usually wear. It's nicely made, and is long enough... but wow I couldn't wait to get out of it by day's end.