Efforts to address the major health, environmental, and social threats that can be found across the globe rely on changes in human behavior. Yet identifying effective and efficient ways to change behavior remains a vexing challenge. To meet this need, investigators need to design and evaluate behavioral intervention strategies in a manner that affords the creation of evidence-based guidelines that specify not only whether interventions work but also how and under what conditions. In this chapter, the design and testing of interventions are situated within the experimental medicine approach. This approach leverages the strength of the experimental method to test how behavior change intervention strategies work and to identify the conditions under which they operate effectively. Moreover, it organizes how investigators specify the questions that underlie the study of behavior change interventions and requires them to articulate precisely what intervention strategy they are using, how they think the strategy operates, and the outcomes it generates. Through the systematic use of this approach, evidence will emerge that addresses practitioners’ prevailing concerns directly – what intervention strategy is the most effective and efficient way to address the problem at hand. This chapter provides an overview of how to implement the experimental medicine approach, describes its key features, and addresses the importance of precision and, finally, considers this approach within a broader set of initiatives that have emerged to support a programmatic approach to the design, evaluation, and implementation of behavior change interventions.

Social problems in many domains, including health, education, social relationships, and the workplace, have their origins in human behavior. The documented links between behavior and social problems have sparked interest in governments and organizations to develop effective interventions to promote behavior change. The Handbook of Behavior Change provides comprehensive coverage of contemporary theory, research, and practice on behavior change. The handbook incorporates theory- and evidence-based approaches to behavior change with chapters from leading theorists, researchers, and practitioners from multiple disciplines, including psychology, sociology, behavioral science, economics, and implementation science. Chapters are organized into three parts: (1) Theory and Behavior Change; (2) Methods and Processes of Behavior Change: Intervention Development, Application, and Translation; and (3) Behavior Change Interventions: Practical Guides to Behavior Change. This chapter provides an overview of the theory- and evidence-based approaches of the handbook, introduces the content of the handbook, and provides suggestions on how the handbook may be used by different readers. The handbook aims to provide all interested in behavior change, including researchers and students, practitioners, and policy makers, with up-to-date knowledge on behavior change and guidance on how to develop effective interventions to change behavior in different populations and contexts.