In the United States accredited residency programs in addiction exist only for psychiatrists specializing in addiction psychiatry (ADP); nonpsychiatrists seeking training in addiction medicine (ADM) can train in nonaccredited "fellowships," or can receive training in some ADP programs, only to not be granted a certificate of completion of accredited training. Information about ADP residency programs has been tabulated, but it is not available for ADM fellowships. The authors conducted a national survey to compile information about the location, structure, curriculum, and other characteristics of active ADM fellowships. Of the 40 accredited ADP residency programs, 7 offered training in addiction to nonpsychiatrists. The authors identified 14 nonaccredited ADM fellowships. In 2009 and 2010, there were approximately 15 nonpsychiatrists in ADP programs and 25 in ADM fellowships. Clinical experiences included inpatient services, outpatient treatment services such as methadone maintenance or buprenorphine maintenance, and providing addiction consult services. The most common academic activities included weekly lectures and the teaching of medical students. (Contains 4 tables.)