Just too large. I bought XL but I think M might work because the fabric has little body. It has a "strip" across the back to hold it on because of the deep V-neck on both sides. It will work just fine for a bothing suit cover-up, but I won't wear it as a maxi dress anywhere else.
This can be worn as a beach cover-up as well as a casual maxi dress. I plan to wear it with a short jacket or sweater on a cruise. Idea: On a cruise, wear it to dinner one night with a short jacket, and use it alone as a cover-up @ the pool the rest of the week - double duty! I am 5'3 and ordered my usual size medium - I like loose rather than tight cover-ups; it fits perfectly except that it does run a bit long, especially in the back - fine with heels, but too long as a cover-up, so I plan to shorten it a hem's width. I like it so much that I just ordered it in black!