I am 5'4", medium frame and got both the small and medium and found that the small was just a little too form fitting. The medium was just a tad bigger, but, it's a sweatshirt and I can layer shirts under it and it still looks good. It's perfect for cool temps and I feel snuggly warm wearing it. I will return the small.
I LOVE this item. Based on the reviews, I went to the retail store to check it out before buying one for my husband who needed a new hooded sweatshirt. I keep borrowing it. The slick sleeves make it easy on and off no matter what you are wearing. It is wonderful. Soft, warm, and heavy duty. Wish the color range included a matching fleece interior but who needs fashion when you have WARMTH! A thought for improvement would be to add a little primaloft under the sleeves to keep the overall design intact.
Great jacket. Very warm and soft. The inside security pockets are fantastic. I bought the mens jacket instead of womens because I wanted a roomier fit. It was perfect.