In addition to my previous review, I would add that my hip is approx. 36", and these shorts have a low rise. The x-small hits me midway between my true waist and my hip.

I am 5'7", and I weigh about 128 lbs. My waist is right around 26". I ordered the XS based on my previous experiences with Icebreaker. Overall, the fit is great. The fabric itself stretches out a bit with wear, and pretty much fits me perfectly; however, in my opinion, the waistband is a tad on the snug side (which seems consistent with Icebreaker size charts). I would order them again, although I might consider going a size up based on the waistband, which I would like to be a bit less constricting.

This is the best underwear ever. They are very comfortable, and are wearable for days, just like they say. The boy cut tends to ride up a little, but not too bad.

I never thought I would like merino underwear but tried a pair after I fell in love with all their other pieces of clothing. They are the most functional underwear I have... comfortable, sweat-absorbent, warm or cool as needed, and never become smelly.
On my shape, the low-rise slips up to my waist and won't stay put on my hips, (maybe because I have a small waist?), but I like them anywhay.

I took these on a backpacking trip to South Africa and I couldn't have asked for more functional undies. They kept my behind warm when it was rainy and windy at the cape, kept me cool during long drives and hikes at Kruger Park. After washing them, they dried faster than microfiber undies (I also had some ExOfficios with me). I like the high waistband coz most of my hiking pants are high in the waist as well,so that works out fine. They do look pretty big when compared to other undies though...my travel mates would give me crap when I hung em up. I love these "granny panties" though and think that they look good when worn...most importantly they perform great.

Soft, comfortable, but why the high waist? These are the hugest pair in my collection, even compared to other boy shorts. There are almost tap pants.

I wasn't sure about wool for underwear, but these Icebreaker boy shorts are soft and comfortable. They keep me cool and dry while hiking with no riding up or chafing. I'm not a fan of the high waistband but their other great qualities more than make up for it.