An ankle support has a tubular sock-like elastic sheath which, in use, is slipped over the foot and ankle of a wearer and extends upwardly over the lower leg, the sheath thereby having lateral and medial sides and a posterior end for receiving the heel of a wearer. Heel locks are provided by lateral and medial elastic locking straps secured to the sheath at a bottom portion of the posterior end of the sheath, and at a rear portion of the sheath (back of the heel) above the posterior end. The action of the two locking straps locks the heel of the wearer against lateral and medial movement. An elastic wrap on the sheath over the foot and ankle of the wearer overlies the lateral and medial portions of the locking straps to provide a lift to the heel.