Following U.S. Food and Drug Administration approval and the issuance of interim guidance documents for oral antiretroviral pre-exposure prophylaxis (PrEP) use in the U.S., there is urgent need to begin addressing the complex, multi-stakeholder, and rapidly evolving (i.e., “wicked”) issues posed for the safe, effective, and appropriately targeted use of PrEP for prevention of the sexual acquisition of HIV infection. In this supplement1–18 to the American Journal of Preventive Medicine, a series of articles is presented from diverse research and implementation disciplines to explore key issues and identify conceptual frameworks, practice models, resources, and experiences to advance the discussion of how best to introduce, disseminate, and evaluate PrEP as a new component of HIV prevention services in the U.S.