I am 5'6", 130lbs, bra size 34B and the size small fit me well. Any larger in the bust and it might be too tight. I had to get white for my CNA program and was worried this would be see through but I have no problem wearing it with just a nude colored bra.

The length was a little long but nothing to be too concerned about. Love the waist-level hook for your badge, and the slit in the neck also works for badges.