Socks are knit with pre-shrunk, color-fast cotton yarns and all of our socks can be machine washed & dried. Socks will shrink a little in their first washing and are actually knit on the large side to accommodate this. The colors will not run or fade. After several washings, stray ends of yarn may work themseleves loose - you may clip these off or tuck them back into the sock. This is normal and the socks will not fall apart.