With rapidly progressing therapeutic methods in the cardiovascular medicine, scientific evaluations for newly developed cardiovascular drugs and therapies have become mandatory. We have launched five large scale multicenter cooperative studies, namely, Japan Multicenter Investigation for Cardiovascular Drugs/Therapies, J-MIC (I), (B), (M), (S), and (K). The aims of studies include to investigate: the best therapeutic approach in patients with acute myocardial infarction who underwent thrombolytic therapy with or without any adjunctive treatment (I), the long-term comparative study (3 years) of nifedipine (extended release tablet) with ACE inhibitor in patients with essential hypertension and ischemic heart disease (B), the long-term effect (3 years) of trapidil and/or ethyl icosapentate in patients with ischemic heart disease with or without arteriosclerotic obstructive disease in terms of progression or regression of atherosclerotic changes in coronary as well as peripheral arteries (M), the efficacy and safety of pravastatin to prevent post-PTCA restenosis (S), and regression of atherosclerotic lesion of coronary arteries in patients with familial hypercholesterolemia by LDL apheresis (K).