The ACC/AHA Task Force on Clinical Practice Guide- lines has commissioned this guideline to consolidate existing recommendations and various recent scientific statements, expert consensus documents, and clinical practice guidelines into a single guidance document fo- cused on the primary prevention of ASCVD. However, this guideline also includes newly generated recom- mendations for aspirin use, exercise and physical activ- ity, and tobacco use, in addition to recommendations related to team-based care, shared decision-making, and assessment of social determinants of health, to cre- ate a comprehensive yet targeted ACC/AHA guideline on the prevention of ASCVD. This guideline has been formatted in the modular chunk format to facilitate readability and future updating. Prevention strategies occur at the population level but must also engage individual adults to slow the de- velopment of ASCVD. The most important way to pre- vent ASCVD is to promote a healthy lifestyle through- out life. Prevention strategies must include a strong focus on lifestyle optimization (improvements in diet, physical activity, and avoidance of tobacco use and ex- posure to secondhand smoke) to minimize the risk of future ASCVD events. A comprehensive patient-centered approach that addresses all aspects of a patient s lifestyle habits and estimated risk of a future ASCVD event is the first step in deciding on where there may be a need for pharmacotherapy. Even if a blood pressure (BP) reduc- ing medication, lipid-lowering medication, or diabe- tes medication is ultimately prescribed, lifestyle goals should be emphasized on a regular basis. Only when a CLINICAL STATEMENTS AND GUIDELINES person s risk is sufficiently high should medications to reduce ASCVD risk be considered as part of a shared decision-making process for optimal treatment. In summary, clinicians and individuals should focus at- tention on living a healthy lifestyle by referring to these evidence-based recommendations to help pre- vent ASCVD. 