Relationships, jobs, and health behaviors-these are what New Year's resolutions are made of. Every year millions resolve to adopt a better diet, exercise more, become fit, or lose weight but few put into practice the health behaviors they aspire to. For those who successfully begin, the likelihood that they will maintain these habits is low. Healthcare professionals recognize the importance of these, and other, health behaviors but struggle to provide their patients with the tools necessary for successful maintenance of their medical regimens. The thousands of research papers that exist on...