The Housing Choice Voucher (HCV) program is the federal government’s largest form of rental assistance, annually subsidizing the cost of private rental housing for over 2.4 million households. This paper provides an overview of the history, operation, and current debates around the HCV program. It considers the program from a policy perspective, focusing on the legislative and programmatic elements that govern its scale and operation, and limit its effectiveness in addressing the housing stability and affordability needs of all low-income renters.