In the 21st century there have been several significant advances in our thinking about health and functioning. These developments are based primarily on the WHO’s International Classification of Functioning, Health and Disability (2001) (the ICF), which provides a modern framework for health. It reminds us that health is manifested by functioning, and that a number of aspects of people’s lives need to be considered together when assessing a person’s situation (and their ‘health’). The ICF recognizes that any health condition has manifestations in ‘body structure and function’. These are called ‘impairments’ and they may interfere with people’s everyday ‘activities’ and limit their ability and opportunity for ‘participation’ (engagement in life in ways that are personally meaningful). The ‘contextual factors’ include many dimensions of the ‘environment’ (human, physical, attitudinal, political and so on), and ‘personal factors’ – specific features of each individual’s life that make them unique. These several aspects of people’s lives are interconnected, reflecting the organic nature of health as a product of all these factors.