This paper examines the trafficking of vulnerable populations in Southeast Asia and the effectiveness of the Association of Southeast Asian Nations in combating human trafficking in the region. Human trafficking is one of the most egregious and persistent human rights violations throughout Southeast Asia, and increases in regional migration and lack of inter-governmental coordination have consistently exacerbated this issue. ASEAN’s establishment in 1967 has since facilitated regional cooperation in Southeast Asia, and with the adoption of the ASEAN Declaration of Human Rights in 2012, the grouping is expected to put greater emphasis on addressing human trafficking issues in the region. This paper critically evaluates the success of ASEAN’s antitrafficking initiatives by researching different trafficked groups in Southeast Asia (labor, sexual, child, etc.),examining the trafficking laws of countries with significant trafficked populations, and assessing the effectiveness of existing ASEAN policies. It is concluded that ASEAN has not yet had a significant impact on reducing human trafficking throughout Southeast Asia. However, increased inter-governmental cooperation and accountability mechanisms promoted by ASEAN may lead to improvements in the future. This research sheds light on the effectiveness of ASEAN as an international human rights actor as well as providing recommendations for the improvement of the organization’s anti-trafficking endeavors.