Epidemiologists have utilized several health care systems with large numbers of enrollees and centralized databases to achieve their research aims. Although containing many of the features that have made certain health care systems valuable to the conduct of epidemiologic research, the US Department of Veterans Affairs (VA) medical care system has not been well utilized by epidemiologists. This article will describe existing and planned features of this health care system that should be of interest to epidemiologists, including centralized databases that capture hospital discharge and outpatient clinic diagnostic data, a planned enrollment file that would contain all persons eligible for VA medical care, and the size and national dispersion of VA medical care facilities. Also, VA leadership has demonstrated an interest in the promotion of epidemiologic research by initiating several new programs, including the creation of three Epidemiologic Research and Information Centers (ERICs) to foster VA epidemiologic research, and announcing a program to support investigator-initiated epidemiologic research projects with VA funding. Epidemiologists with interests in medical problems that afflict veterans should consider partnerships with VA investigators to achieve their research aims. Am J Epidemiol 2000; 151: 307–14.