Background: This paper critically reviews the concept of "professional responsibility" in physical education. The paper is rooted in the belief that the physical education profession has, by virtue of its expertise in young people and physical activity, the potential to deliver a broad range of desirable educational and health-related outcomes. Yet, if the physical education profession is just that--a "profession"--then its true potential lies in its ability to serve its "clients"; children and young people. In order to serve its clients effectively, therefore, each member of the profession has a responsibility to base its practices upon the best knowledge available at any given time. Key concepts: Physical education teachers as professionals are considered as learners--rather than as teachers. The development of this argument is traced through the work of John Dewey, Donald Schon, David Hargreaves and the recent national Teaching and Learning Research Programme (TLRP) in England. On being a profession: The nature of professions is then analysed and an holistic view of the physical education profession is suggested which places teachers at the core of a community of practice. Career-long professional development (CPD) is identified as a defining characteristic of all professions, yet it is argued that much of the CPD traditionally offered to physical education teachers is limited in both scope and challenge. Health and positive youth development: The problems resulting from ineffective and inappropriate PE-CPD are considered. Expectations on the PE profession are increasing, nationally and internationally, in two areas of public concern--health and positive youth development. It is argued, however, that the fractured nature of the wider profession means that PE teachers are poorly prepared to deliver what is expected of it in these two areas. Implications for the PE profession: The implications of a fractured profession are explored and it is argued that urgent changes are required to the ways in which teachers learn, teacher educators (from ITT to CPD) support professional learning, and researchers undertake, disseminate and are held accountable for their research. Conclusion: The extended profession needs to find ways to work together more effectively to support teachers who exist to serve the clients of this profession: children and young people. It is suggested that one way to start this process is to refocus teachers on themselves as career-long learners, and then to consider the implications for the work of the wider PE profession; including researchers.