Attitudes are people’s stored evaluations of entities (e.g., behaviors, people, ideas, objects). Attitudes are interesting from a behavior change perspective, given theory and research suggesting that attitudes guide behavior; thus, changing attitudes may be an effective means to change behavior. This chapter provides an overview of the attitude change literature and interventions targeting attitude change in order to change behavior. The chapter also provides example materials used in attitude-based behavior change interventions across a broad range of behaviors. First, the chapter provides an overview of the conceptualization and measurement of attitudes and the psychological theories that have been employed to explain how attitude change occurs. Next, research evidence of various attitude change techniques is reviewed, including information provision, communication-persuasion, and cognitive dissonance approaches. In addition, step-by-step instructions for select attitude change techniques are provided as templates for interventionists to formulate effective attitude change interventions. The chapter also provides a range of evidence-based materials that can be delivered in a variety of delivery modes (e.g., face-to-face, online, mass media). Finally, a review of the evidence on the effective implementation of these techniques is presented. The chapter concludes with a summary of the attitude change literature and presents some challenges and future directions in moving the attitude research forward.