I am 5'8" and weigh 166. I purchased the size 12 (normally wear a size 10) because sometimes the designer dresses run small. I ended up returning this dress for two reasons. First, the color is not a true yellow, more greenish. Second, the dress was larger up top but fit in the hips. The quality is amazing and the dress is fully lined. I returned because it just did not fit right. I may try the size 10, but when it comes on sale.