and to include a variety of different studies carried out over the last 20 years. Additionally, this article will review the existing literature and discuss the contemporary themes of trafficking addressed within it. This article also aims to discuss current research that exists and take note of research gaps so that we can improve our practices and policies regarding human trafficking in the United States. After a brief summary of the exact study selection methods, the remainder of the review will review the ten selected quantitative studies and what they suggest. So, in this article, the literature will show and discuss the possible factors in a country that lead to human trafficking, how and why these offenders commit this specific crime, and what are the research gaps in the literature and how we we can possibly fix it.