These pants fit me like a glove - with or without a base layer. They are somewhat low rise and fit more like a contemporary pair of jeans than other ski pants I've tried. For reference, I'm an hourglass 5'8", 150lbs with a pretty curvy bum and these fit me perfectly in a medium (which was sometimes too small in other brands). Used them on a 5 day ski trip to CO - 4 days of skiing and one snowmobiling. Looked good as new after a washing. These were plenty warm with a base layer on a 15/20 degree snow stormy day. Highly recommend.