This chapter discusses the American College of Cardiology/American Heart Association/ Heart Rhythm Society (AHA/ACC/HRS) and European Society of Cardiology (ESC) guidelines for atrial fibrillation (AF) management with particular focus on antiarrhythmic drug (AAD) selection and the identification of individuals for whom AAD treatment is appropriate. Discussion includes AAD indications, when to start an AAD, choosing among AADs, how to minimize proarrhythmic risk, how to determine efficacy, and the use of adjuvant interventions. The indications for all AADs are based on safety; the current AHA/ACC/HRS and ESC guidelines state that the choice of AAD is based on the presence or absence of structural heart disease (SHD), coronary artery disease, or heart failure (HF), with further recommendations in the ESC guidelines based on HF type (e.g., HF with reduced ejection fraction [HFrEF] versus HF with preserved ejection fraction [HFpEF]). The chapter closes with a discussion of the lack of consistent use of guideline-directed care, with a review of supportive data from the recently reported AIM-AF survey—a multinational survey on AF management that involved both cardiologists and electrophysiologists. In AIM-AF, inappropriate drug selection in terms of suitable candidate selection and drug choice occurred with all types of drugs and in most patient groups. Most notable was the overuse of amiodarone in patients without SHD, and the widespread use of sotalol, including its use in patients with HFrEF. Chapter 5 is summarized as follows: