Sport provision is best understood as a series of distinctive domains, with characteristic purposes, motivations, practices and demands on coaches’ expertise. This paper identifies the characteristics of the instructor-led adult participation coaching domain, which is the least well researched and developed, and identifies the implications for coach education and workforce management. The propositions are illustrated by conversations with Coaching Development Managers from 8 sports in the UK that have a significant adult participation profile. The paper confirms the variety of domain populations, from casual recreation to coach-dependent adult competition, including ‘Masters’-designated participation, but outside the mainstream of performance sport. It highlights two principal coaching practices: market-led sport instructors, delivering episodic, largely technique-based ‘lessons’ to participants, and (club) coaches of adult competition sport. However, much of the characteristic adult participation is casual recreation and coach-independent. The paper argues that a fuller understanding of this domain is important for ensuring that coaches’ expertise and practice are matched to participant needs
