Based on data from the Turkish Society of Cardiology and others, it is established that Turks have a high prevalence of coronary heart disease (CHD). Several risk factors are prominent in Turks: dyslipidemia, cigarette smoking, and hypertension. The dyslipidemia is unique in that very low levels of HDL-C and typically "normal" LDL-C levels characterize the Turkish population. The low HDL-C levels appear to be genetic in origin and are largely independent of high triglyceride levels (73% of Turkish men and 94% of women with HDL-C <40 mg/dl have triglyceride levels <150 mg/dl; only 15% of men and 3% of women with HDL-C <40 mg/dl have triglyceride levels >200 mg/dl). HDL-C levels are 10-15% mg/dl lower in Turks than seen in the United States or western Europe. Low HDL-C is a major risk factor; CHD risk increases 2-4% for every 1 mg/dl decrease in HDL-C levels. Existing treatment guidelines focus on plasma LDL-C levels and fail to take into account the continuous increase in CHD risk that occurs as HDL-C levels decrease. However, several studies show that patients with CHD or free of CHD but with multiple risk factors, who have low HDL-C and near optimal LDL-C, benefit very significantly from lipid-lowering therapy. Many of these patients with low HDL-C levels do not qualify for drug therapy based on existing guidelines. Therefore, we believe that unique guidelines must be developed to guide the treatment of low HDL-C Turkish patients. We suggest that treatment based on both the LDL-C level and the total cholesterol/HDL-C (TC/HDL-C) ratio is the best way to address treatment of patients with low HDL-C levels. The most effective drug treatment available presently in Turkey relies on lowering LDL-C levels to optimize the TC/HDL-C ratio.