I bought this in a size Medium for my husband. He loves it! It is a great under-layer when he goes hunting, but he also wears it around the house like pajamas. The only set-back is that the body portion is HUGE. He is 5'8" with broad shoulders and a narrow waist. The medium is appropriately snug on his arms and legs. But the torso is so baggy it looks like the suit was meant to fit a man with a Santa Claus belly. If I'd gotten a small it would be too tight in his shoulders & armpits. If we could just chop out about 5 inches of material in the middle of the suit it would be a perfect fit.