The Substance Use Research Core (SURC) offers services and expertise on the methods needed to develop and conduct effective substance use/HIV research. Services are directed at: 1) hypothesis generation, 2) assessment, 3) intervention development. The SURC offers expertise in state-of-the-art methods for assessing and analyzing substance use and developing and implementing interventions to address alcohol, tobacco, and other substance use. The SURC serves as a regional and national resource on substance use/HIV research by connecting substance use investigators with HIV investigators through formal and informal opportunities through the Inter-CFAR Substance Use Research Community.