My work shirt/uniform is a small. I'm 6 foot so I'm usually a medium, but I started with that and it was a tent! I decided to wear a small instead, but the sleeves aren't as long as I'd like, but at least it fits a little better. If I had any money I'd get a medium and have it tailored, but that's an expense i can't afford (and I don't know if it would look any good as I've never had anything tailored)