This chapter examines understandings of social and emotional wellbeing (SEWB) with the aim of clarifying the relationship between SEWB, mental health and mental health disorders from an Aboriginal and Torres Strait Islanders’ perspective. The chapter begins with a brief historical overview of how the term ‘social and emotional wellbeing’ emerged as a signifier of Aboriginal and Torres Strait Islander concepts of health. We define SEWB as a multidimensional concept of health that includes mental health, but which also encompasses domains of health and wellbeing such as connection to land or ‘country’, culture, spirituality, ancestry, family, and community. The domains and guiding principles that typically characterise SEWB are outlined and situated within a framework that places Aboriginal and Torres Strait Islander world views and culture as central. The importance of recognising social, cultural, historical and political determinants in shaping Aboriginal and Torres Strait Islander SEWB is also discussed. We suggest that working within a SEWB framework involves developing an understanding of how these principles, domains and determinants manifest and operate at a local level, and explore how to apply these in a practical setting.