A leg ulcer is defined as a loss of skin below the knee, which takes more than six weeks to heal [Fig 1]. Venous leg ulcers are caused by sustained high pressure within the venous system of the leg. Over half are caused by progressive venous reflux that begins as varicose veins, and the remainder develop after a deep vein thrombosis. The key to effective management is accurate assessment of risk factors to enable the appropriate diagnosis to be made and the use of compression therapy to reduce the venous hypertension. In order to achieve this there are a number of important factors to consider.