Let me first say I used to love this shoe. I wore them all the time. I loved my Drainmaker 1 and still do. However, after my wife put the Drainmaker 2 in the washer (but not the drier) they totally collapsed. The rear heal portion flopped over and now looks like a half fallen tree. I don't see anywhere on the shoe that says you can't wash them in a washing machine. I washed my Drainmaker 1 lots of times. All I can say is if you need to wash them, do it by hand to be safe. Otherwise your foot won't even fit back in the shoe. See photo.