The authors demonstrate that marketing actions, such as pricing, can alter the actual efficacy of products to which they are applied. These placebo effects stem from activation of expectancies about the efficacy of the product, a process that appears not to be conscious. In three experiments, the authors show that consumers who pay a discounted price for a product (e.g., an energy drink thought to increase mental acuity) may derive less actual benefit from consuming this product (e.g., they are able to solve fewer puzzles) than consumers who purchase and consume the exact same product but pay its regular price. The studies consistently support the role of expectancies in mediating this placebo effect. The authors conclude with a discussion of theoretical, managerial, and public policy implications of the findings.