I followed the other reviews and sized down. normally, i'm a small/medium in retailer (5'8"/135 for clarification) and i expected the garment to be a bit roomy. i ordered the small and when it arrived i almost called the corporate office to ensure i didn't have to pay rent on the romper, given that you could comfortably fit a small family of five in it. oddly, the arm-holes were normal sized? i returned this mess.