In 2004, a new initiative began between the International Organization for Migration (IOM) and the U.S. Department of State's Bureau of Population, Refugees, and Migration (PRM) to develop performance indicators for counter-trafficking (CT) projects. As part of continued efforts to improve the quality and assess impact of its counter-trafficking work, IOM has worked closely with the U.S. Government to develop performance indicators within the programming context of trafficking in persons. This effort has been field and experience driven with the goal of developing monitoring and evaluating systems and establishing institutional guidelines for measuring the short, medium and long-term impacts of counter-trafficking work. It is hoped that this handbook will be useful for government and non-governmental stakeholders and service providers for establishing performance indicators for counter-trafficking projects that can be compared across countries and regions, and ultimately assist in effective and successful programming.