This article discusses the historical emergence of notions of old age and third age as identity categories linked to the process of ageing. Their emergence can be understood as a result of a complex combination of factors such as medical and social knowledge, management agents, political movements and economic interests. By taking old age and third age as historically determined age identities, we seek to trace out the formation of these identities the article analizes the factors that determined their emergence and how they have grown and gained legitimacy. As an age category, 'old age' has its roots mainly in medical knowledge specialized in the study of the aged body, and the appearance of retirement. The 'third age' age category derives mainly from the specialization of the agents of management for ageing, the advocatory discourse of social gerontology and the interests of the consumer culture. These are the categories that are currently available to identify, define and, more recently, transform the process of contemporary ageing.
age identity; ageing; third age