They stay above the knee pretty well.  Occasionally movement like climbing up stairs or running will make them slide a little, but never below the knee, so I still adjust perhaps twice a day, which isn't a big deal since I generally go the bathroom more often than that!  Other than that they are really comfortable, don't pinch, and keep me warm enough not to need tights over them, and they look really good.  The husband likes it!

For reference, I am 5"3' and 103 lb.  These are just the right length for me, so, not sure if they would work for taller people.