Tests to differentiate recent from long-standing infections known as Recent Infection Testing Algorithms (RITA) have become an increasingly attractive approach to monitoring recent HIV infections and are used for estimating HIV incidence in several countries. This literature review provides a range of estimates in key populations, highlighting studies that have employed a RITA assay to distinct populations in order to produce estimates of HIV incidence, and pays particular attention to variations in assays, settings, window periods, and methods of analysis. Estimates of HIV incidence across populations most at risk were generally below 1 2% per year, and below 4% per year among attendees of STI clinics and similar high-risk settings. Estimated HIV incidence rates among men who have sex with men were generally less than 5% per year, similar to those reported among migrant populations and ethnic minorities.