Atrial fibrillation (AF) is an increasing burden worldwide. However, AF prevention has not been emphasized enough in clinical practice or guidelines. In this paper, the authors review the associations of modifiable lifestyle factors, including alcohol abuse, smoking, physical inactivity, and unhealthy psychological stress, with the risk for AF development. The authors also review the associations of cardiovascular risk factors that can be bettermanaged, including obesity and overweight, high blood pressure, diabetes, dyslipidemia, obstructive sleep apnea, and other cardiovascular diseases, with the risk for AF. The conclusion is that a high proportion of AF can be prevented by combining strategies, focusing on the high-risk population for better risk factor management, and emphasizing healthy lifestyle choices in the whole population. (J Am Coll Cardiol 2017; 69: 1968-82) (C) 2017 Published by Elsevier on behalf of the American College of Cardiology Foundation.