Elevated levels of serum cholesterol have long been associated with an increased risk of both the occurrence and the progression of coronary atherosclerosis. The use of dietary therapy to reduce elevated lipid labels has received widespread attention, but like other therapy requiring behavioral modification has met with only partial success in most patients. Little wonder that drugs which lower lipids have been utilized to supplement the effect of diet in hyperlipidemia subjects. Currently available hypolipidemic agents are far from ideal in their effectiveness and lack of side effects, so the search for more potent, safer drugs has been intense. This paper reports on the use of one such agent, gemfibrozil; and its comparison with clofibrate and placebo. Gemfibrozil (CL719, 2,2-dimethyle-5-(2,5 xylyloxy) valeric acid is a substituted phenoxy alkyl acid which has been shown to decrease lipids in hyperlipidemia subjects. A short term study using 1200 mg of gemfibrozil daily demonstrated reduction in total serum cholesterol, triglyceride and apo B levels, and a concomitant rise in HDL cholesterol levels. A long term study of the effect so gemfibrozil showed that the drug had a more pronounced effect on triglyceride then cholesterol, that it had few side effects and the effect was sustained. A recent study from New Zealand demonstrated that gemfibrozil, compared to placebo, lowered plasma cholesterol, triglyceride and VLDL levels and raised HDL levels.