We provide an overview of what is known about the impact of direct-to-consumer (DTC) advertising of prescription drugs. Specifically, we explore the historical trends that led to the industry's increasing use of this form of promotion. Then, using the published literature to date, we review the impact of DTC advertising on the consumer, the medical profession, and the health care system. We conclude by offering policy suggestions for how the pharmaceutical industry can promote its products more responsibly, how the Food and Drug Administration (FDA) can regulate DTC advertising more effectively, and how the medical and public health communities can educate the public about drug therapies more constructively.