BACKGROUND: The prevalence of atrial fibrillation (AF) continues to increase; however, there are limited data describing the division of care among practitioners in the community and whether care differs depending on provider specialty. METHODS AND RESULTS: Using the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF) Registry, we described patient characteristics and AF management strategies in ambulatory clinic practice settings, including electrophysiology (EP), general cardiology, and primary care. A total of 10 097 patients were included; of these, 1544 (15.3%) were cared for by an EP provider, 6584 (65.2%) by a cardiology provider, and 1969 (19.5%) by an internal medicine/primary care provider. Compared with those patients who were cared for by cardiologists or internal medicine/primary care providers, patients cared for by EP providers were younger (median age, 73 years [interquartile range, IQR, 64, 80 years, Q1, Q3] versus 75 years [IQR, 67, 82 years] for cardiology and versus 76 years [IQR, 68, 82 years] for primary care). Compared with cardiology and internal medicine/primary care providers, EP providers used rhythm control (versus rate control) management more often (44.2% versus 29.7% and 28.8%, respectively, P<0.0001; adjusted odds ratio [OR] EP versus cardiology, 1.66 [95% confidence interval, CI, 1.05 to 2.61]; adjusted OR for internal medicine/primary care versus cardiology, 0.91 [95% CI, 0.65 to 1.26]). Use of oral anticoagulant therapy was high across all providers, although it was higher for cardiology and EP providers (overall, 76.1%; P=0.02 for difference between groups). CONCLUSIONS: Our data demonstrate important differences between provider specialties, the demographics of the AF patient population treated, and treatment strategies-particularly for rhythm control and anticoagulation therapy.