Cost-effectiveness and cost-utility analyses are defined and examples given of their use in a trial comparing the use of propranolol with verapamil. Eight other analyses are considered that look at the cost-effectiveness of anti-hypertensive treatment in general and at comparisons of such treatments. The analyses are examined to see if conclusions are made for different ages and both sexes; whether compliance with treatment is considered, and whether discounting, the cost of treating side effects and the effects of cholesterol were considered. The methods of estimating life years gained are examined and, if epidemiological data were employed, the fraction of benefit (FOB) assumed. The levels of blood pressure are examined together with the methods of estimating the quality of life adjusted years of survival (QALYS) in cost-utility analyses. It is concluded that large trials are required in which both survival on different treatments is measured together with costs and the quality of life of the individual patients. Cost-effectiveness and cost-utility is more favourable in men than women and in the elderly. There is no agreement as to which drug group has the most advantageous cost-utility.