Abstract: The aim of this chapter is to uncover the discrepancy between the important role that responsibility appraisals play in the applied health-related fields and their low status in current theoretical and empirical research. A theoretical model with supporting empirical results is presented to demonstrate and overcome this gap. Three facets of the social phenomenon of health-related responsibility are discussed: (1) responsibility as an important key construct which can predict traditional health behaviour (e.g. regular use of annual health check-ups), as a tool for widening the scope of (2) the analysed behaviour and (3) its underlying motives. Health behaviour and its motives are not restricted to behaviour that serves one’s own health; rather, it also encompasses commitments and behavioural decisions to reduce health risks for the general public and to protect health on a more global societal level (e.g. supporting public health campaigns). The chapter concludes with a discussion of the implications for an expansion of health models by the inclusion of the complex social phenomenon of responsibility.