I generally wear one pair of socks when I play, which was fine with my old pair of Wilson shoes. I got a pair of Barricade 4's yesterday and they fit really well, but my heel slides up and down a bit in back, so my coach suggested wearing two pairs of socks when I play. He wears two pairs as well. Today I was watching the Federer/Nadal final in Germany and I noticed Federer was wearing two pairs of socks as well, so I was curious how many of you out there wear two pairs of socks as well. Thanks for any input.