Foods purchased from prepared food sources (ready-to-eat foods that can be eaten outside the home or brought back or delivered to the home to eat) are now a major part of the American diet and are linked to increased rates of overweight and chronic disease. Prepared food sources may be an important venue for obesity-prevention efforts. This is the first systematic review of interventions in community-based prepared-food sources. Researchers found that interventions in prepared-food sources show initial promising results at the store level. Interventions mostly targeted an urban population, predominately white, in a range of incomes. The most common framework used was social marketing theory. Most interventions centered on signage to promote existing healthful food choices. Several worked with kitchen staff to improve low-fat food preparation practices, and several conducted formal menu analyses to determine more healthful food choices for promotion. Many interventions showed that changing the prepared-food environment may improve sales and awareness of more healthful foods and improve purchasing and consumption behaviors.