Lipid disorders are the most important factors in the development of coronary heart disease (CHD). They need to be treated in primary as well as in secondary prevention. U.S. and European Consensus Conferences agreed that desirable serum cholesterol levels should not exceed 200 mg/dL. When baseline cholesterol averages above 250 mg/dL, the minimum requirement for characterizing the lipoprotein disorder is measurement of cholesterol, triglycerides, and highdensity lipoprotein (HDL) in the fasting state. In selecting targets for serum lipid values, it may be taken into account that CHD incidence is lowest in persons with serum cholesterol below 180 mg/dL. Any kind of lipid-lowering therapy should be commenced with dietary treatment. If this is ineffective, drugs may be applied additionally. Possible causes of secondary hyperlipidemia should be excluded. There is no strict age limit for treatment but the subject's cardiovascular status should be examined carefully, especially in secondary prevention. The patient in whom extensive myocardial damage is the main arbiter of prognosis is unlikely to gain from strenuous efforts aimed at retarding progression of atheromata, the major causes ofCHD. A simple classification distinguishes drugs with a predominant effect on hypercholesterolemia from those effective in endogenous hypertriglyceridemia but with a somewhat weaker cholesterollowering action. Using lipid-lowering drugs, their indications and side effects should be considered.