I ordered the size large based on the size chart provided. I'm 5'7" and currently weigh about 140, with a 40" bust, 30" waist, 39" hip. I have slightly broad shoulders and long arms, which can be a problem, but not with this jacket! The proportions and fit are great for me. It has princess seams, so it is not boxy at all. It's roomy but not huge, and I can comfortably wear a Lands End size medium(10-12) fleece jacket underneath it if I need to. I purposely bought this for spring/summer/fall, so I'm glad it is lightweight and not bulky or lined. I'll be taking it with me to the beach and other outdoor activities and throwing it over shorts and tank top when it gets windy or rainy. I'm in New England, which has been very rainy all spring, so this is exactly what I needed. Sometimes a longer, lined parka is just too much.
The only problem is I think I was sent a jacket that was marked to be sold as a second, not first quality, because there were some pieces of tape inside, correlating to some loose stitching that are visible on the outside, and under one arm, where the seams don't meet up evenly. Also, inside on the shoulder/neck seam, there is loose thread, and the edge of the material has a slight tear. For this reason, I will be exchanging it for another, of the same size and color, and hope I get a first quality version. I will update my review when i receive my replacement. See pictures for details. Also, I love the color(purple), which I was afraid might be too much of a pastel, but it is a vibrant, flattering color.