This is a Junior size so it makes sense that it runs a bit small. For ladies, order a size up. The fabric on the sleeves is not stretchy, more like a rain jacket. It looks like it would be soft and comfy, more like cotton but there are two fabrics on the jacket. It makes it a bit tight in the arms for me. Wish it was a stretch fabric under the arms not a stiffer non-breathable fabric? Doesn't make sense. LOVE the style and the cinched waist. Wish there was a Large in stock so I could order a size up.