This issue of Cardiac Electrophysiology Clinics, Guest Edited by Drs. Mohammad Shenasa, Prashanthan Sanders, and Stanley Nattel, is dedicated to Risk Factors in Atrial Fibrillation: Appraisal of AF Risk Stratification. This is one of four issues selected each year by the series Consulting Editors, Ranjan K. Thakur and Andrea Natale. Topics include, but are not limited to, Epidemiology of Atrial Fibrillation; Hypertension, Prehypertension, Hypertensive Heart Disease and Atrial Fibrillation; Pulmonary Disease, Pulmonary Hypertension and Atrial Fibrillation; Heart Failure with Preserved (HFpEF) and Reduced (HFrEF) LV Systolic Function, Diastolic Dysfunction; Coronary Artery Disease; ECG and Echo Abnormalities in Patients with Atrial Fibrillation Risk Factors; Diabetes and Endocrine Disorders; Obesity and Metabolic Syndrome in Atrial Fibrillation; Renal Disease; Sleep Apnea and Atrial Fibrillation; Channelopathies in Atrial Fibrillation; Implications of Inflammation and Myocardial Fibrosis in Atrial Fibrillation; Role of Biomarkers in Atrial Fibrillation; Left Ventricular Hypertrophy and Other Cardiomyopathies in Atrial Fibrillation; Atrial Fibrillation in Valvular Heart Disease; Atrial Fibrillation in Adult Congenital Heart Disease; Exercise and Athletic Activity in Atrial Fibrillation; Post-op Atrial Fibrillation; Autonomic Dysfunction and Neurohormonal Disorders in Atrial Fibrillation; Social Risk Factors; Atrial Fibrillation and Stroke; Screening for Atrial Fibrillation Risk Factors; Primary Care and Internists Perspective on Atrial Fibrillation Risk Factors; and Lifestyle as a Risk Factor for Atrial Fibrillation.