Strokes occur when blood flow to part of the brain is interrupted. Patients are often bedbound for several days or weeks although if they survive, most will make some recovery. The lack of mobility encourages blood clots to form in the legs − so called deep venous thrombosis or DVT. About 10% of patients will develop these. Pieces of this clot may break off and can be carried by the bloodstream to the lungs. These clots, called pulmonary emboli, can stop the heart and can cause patients with stroke to die suddenly. A treatment which reduces the risk of DVT after surgery is intermittent pneumatic compression (IPC). Inflatable sleeves wrapped around the legs inflate at intervals squeezing blood up the legs, increasing the blood flow, and decreasing the likelihood of clots forming − at least that is the theory!. Although this sounds uncomfortable, most people actually quite like the sensation! There have been some small randomised trials of IPC in stroke patients, particularly those with intracerebral bleeding. However, these studies although encouraging have not provided enough information to persuade clinicians to use this treatment routinely in stroke units. The proposed study will include 2000 patients who have had a stroke and who have been admitted to a stroke unit.