A neurologist writing in 1978 on the treatment he would want if he had a transient ischaemic attack advised that the blood pressure should be checked and investigations instituted to prevent further ischaemic attacks which might culminate in stroke or death.1 The article did not mention health gain and cost, because in 1978 disease based healthcare purchasing was confined to a few underexploited treatments. Health purchasers today, however, have to judge the value of carotid endarterectomy against other attempts to reduce the burden of morbidity from stroke. These include screening for and control of hypertension, antiplatelet therapy using aspirin, and rehabilitation and caring for people who have had a stroke.