Health-relevant communications can be framed in terms of the benefits (gains) or costs (losses) associated with a particular behavior, and the framing of such persuasive messages influences health decision making. Although to ask people to consider a health issue in terms of associated costs is considered an effective way to motivate behavior, empirical findings are inconsistent. In evaluating the effectiveness of framed health messages, investigators must appreciate the context in which health-related decisions are made. The influence of framed information on decision making is contingent on people, first, internalizing the advocated frame and, then, on the degree to which performing a health behavior is perceived as risky. The relative effectiveness of gain-framed or loss-framed appeals depends, in part, on whether a behavior serves an illness-detecting or a health-affirming function. Finally, the authors discuss the cognitive and affective processes that may mediate the influence of framed information on judgment and behavior.