Atherosclerotic cardiovascular disease (ASCVD) is one of the leading causes of death worldwide and in Taiwan. It is highly prevalent and has a tremendous impact on global health. Therefore, the Taiwan Society of Cardiology developed these best-evidence preventive guidelines for decision-making in clinical practice involving aspects of primordial prevention including national policies, promotion of health education, primary prevention of clinical risk factors, and management and control of clinical risk factors. These guidelines cover the full spectrum of ASCVD, including chronic coronary syndrome, acute coronary syndrome, cerebrovascular disease, peripheral artery disease, and aortic aneurysm. In order to enhance medical education and health promotion not only for physicians but also for the general public, we propose a slogan (2H2L) for the primary prevention of ASCVD on the basis of the essential role of healthy dietary pattern and lifestyles: "Healthy Diet and Healthy Lifestyles to Help Your Life and Save Your Lives". We also propose an acronym of the modifiable risk factors/enhancers and relevant strategies to facilitate memory: " ABC2D2EFG-I'M2 ACE": Adiposity, Blood pressure, Cholesterol and Cigarette smoking, Diabetes mellitus and Dietary pattern, Exercise, Frailty, Gout/hyperuricemia, Inflammation/infection, Metabolic syndrome and Metabolic dysfunction-associated fatty liver disease, Atmosphere (environment), Chronic kidney disease, and Easy life (sleep well and no stress). Some imaging studies can be risk enhancers. Some risk factors/clinical conditions are deemed to be preventable, and healthy dietary pattern, physical activity, and body weight control remain the cornerstone of the preventive strategy.