Off-label drug or medical device “use” is the practice of prescribing drugs or medical devices to patients for a purpose not included on the federally approved label. Off-label “marketing” is the practice of attempting to influence physicians to prescribe drugs or devices for off-label purposes. The Federal Food and Drug Administration (FDA) maintains regulatory authority over the proper labeling of drugs and medical devices. This paper summarizes the FDA’s position on off-label use, promotion, and marketing and provides a summary of recent enforcement actions by the U.S. Department of Justice regarding off-label marketing