These sleep shorts are nice quality and fit true to size with the exception of the waistline elastic which is overly soft.  Use of the waistline tie string is mandatory to avoid "losing your britches" when you may not want to be feeling the breeze. I had considered returning them for one size smaller, but no one wants to sleep in tight clothing so I did some home tailoring to take in the waistline. If you are between sizes, choose the smaller.