In 2011, the Department of Health (England) will publish revised You're Welcome criteria. This is the first comprehensive attempt to define good quality health services for young people (11-19 years) and provide a self-assessment tool applicable to all adolescent health services. It builds on a growing understanding of the distinctiveness and importance of adolescent health, and the demands placed on adolescent health services. This article reviews changing understandings of the nature of adolescence, including physical, psychological and social transition, evolving patterns of morbidity and mortality, adolescence as part of a life-course approach to health and health behaviours, and the specific needs of young people when using health services. We describe key features of the You're Welcome criteria and discuss the views of young people and professionals involved in revising them, as well as relevant published literature. Lastly, we discuss how the perspective of social paediatrics may be useful in guiding professionals towards a more holistic approach to adolescent care in the future.