An extensive body of literature has analyzed the individual impacts and collateral consequences of mass incarceration. However, few studies explore the consequences of a parallel and overlapping system: mass immigration detention and deportation. The last 30 years witnessed a dramatic increase in the number of noncitizens detained in and deported from the United States. Individuals detained under immigration laws are held pending adjudication, often mandatorily, and without many basic constitutional protections. Immigrant detention and deportation impose severe burdens on immigrants and their households and levy significant costs to society—financially, as well as in terms of social capital and community well-being. Chiefly due to the difficulty in accessing noncitizens in the process of detention and deportation, this system has largely escaped sociological inquiry. This article provides a background for understanding the growth and consequences of detention and deportation in the United States. It reviews the literature on these immigration law enforcement programs and suggests topical and methodological directions for future research.