Since the early 2000s, a significant number of programs and policies have been developed and implemented to prevent and combat human trafficking. At the international, regional and national levels, government, and international, and nongovernment organizations have established plans of action, conducted training, developed policy tools, and conducted a variety of other activities to counter the phenomenon of trafficking in persons. However, only a small number of these anti–human trafficking interventions have been evaluated and an even fewer number have been evaluated rigorously. This article explores the approaches that have been used to evaluate anti–human trafficking interventions. Through a review of 49 evaluations, the study finds that action is required to increase quality evaluations of anti–human trafficking programs in order to ensure that programs are targeted, implemented, and delivered effectively, and the knowledge on the impact of programs is improved.