I was somewhat skeptical due to the lack of a sizing chart (I can be a medium/large and a size 4-8 depending on the manufacturer) but my 33" hips and 38" posterior fit nicely into mediums (which, I enjoy a nice hug). It's pricier than your standard Hanes 3-Pack, but it's well worth the just for the initial feeling of a God caressing you with the tender love and affection that is this fabric. I fully intend on buying more of these so I may wear them every day, maybe even 24 hours a day, including showers.
On a side note: By "size chart" I meant waist measurements.