I know my measurements - they haven't changed since I decided on prom shirts 7 years ago; 15 1/2, 32-33. This is a typical average size. Instead they sent me an "average" 34-33, with no neck measurements. There was too much material on the chest and there was almost no "tail" to tuck in the front or back of the pants. On average you should order one size smaller, obviously sizes have changed in the last ten years.