I gave up wearing women's trouser socks years ago because they weren't warm, didn't stay up, and weren't comfortable. I solved the problem by buying men's socks in the small size. But "small" men's socks are hard to find in stores, and the next size up is too long for my foot (which ain't dainty, let me tell you).

These wool and cotton blend socks are wonderful. A little large in the foot straight out of the packaging, but after one wash, they fit like they were made for me. They have nice, cushy heels and toes, they're warm and cozy, and they come all the way to my knees and stay there.

For the record, when I buy sneakers/exercise shoes/"tennis" shoes, I usually go to the men's department and buy a size 7 US. My women's shoe size is 8.5 US.