While I love this coat and it served its purpose on my winter break trip to Indiana with -20F temps, it was slightly larger than I would have liked. I am 57 and 125lbs of lean muscle...after reading the Reviews I bought a small and found it to be loose. Its okay if you're planning to wear a lot of layers under it, but Im certain an extra small would have been much better. For size comparison I typically wear a size 2 or size 4 (loose usually). I hope this helps other slim women make a better sizing decision. The zipper is a bit difficult to get going; I definitely cursed it a few times. It takes patience, but works fine. Overall, its a great coat, long, warm, light weight and soft and squishy.