This chapter discusses the role of social factors in ill health, with a particular focus on depression. Major life events increase the risk of most depressive disorders. In a longitudinal study carried out in the early 1980s of 400 mothers in Islington, 1 in 10 developed a depressive disorder within a year, and most of those had a severely threatening life event not long before. This chapter also summarises the three forms of meaning relevant for the aetiology of depression. First, the role-based meanings of severe events relate to traditional anthropological and sociological concerns. Second, the evolutionary-derived meanings show that the experience of humiliation following a severe event is critical in the development of depression. Finally, the memory-linked emotional schemas influence a person's vulnerability to events.