Since the first epidemiological evidence on the benefit of lipid reduction in coronary heart disease (CHD) was gathered, a number of questions have emerged in this field of research. Consistent findings across a number of landmark trials have shown that lipid-lowering therapies significantly reduced major subsequent cardiovascular events in coronary patients with high and moderate low density lipoprotein (LDL) blood cholesterol levels. Although there has been some confusion on the effect of lipid intervention on mortality, recently definite answers have come from several major trials that establish a clear decrease in coronary death for patients after reduction of plasma cholesterol levels. Primary prevention in individuals with high LDL cholesterol levels was shown to be beneficial in terms of cardiovascular event reduction; more data are needed to address this issue for subjects with moderate LDL cholesterol levels. Reduction of LDL cholesterol below normal levels appeared to be beneficial for coronary patients, but again, further research is needed to elucidate this point. To date, major trials have answered some of the many questions pertaining to lipid-lowering therapies; further research will continue to provide information and allow patients to benefit maximally from lipid interventions.