Sport is a developing setting and a relevant system in health promotion but there are few examples of settings-based initiatives and systems thinking in sport. The Gaelic Athletic Association (GAA) Healthy Club Project (HCP) adopts a settings approach delivered through and by grassroots clubs who respond to local needs while working within a national support system. The aim of this evaluation was to assess and describe the health promotion impact and experience of the HCP. Healthy Clubs (n = 23) and Control Clubs (n = 10) completed a Healthy Club Questionnaire at the start and end of the 20-month HCP and Healthy Clubs took part in focus group discussions. Healthy Clubs, using the structures of the HCP, a commitment to health and community engagement, demonstrated a significant improvement in their overall orientation to health promotion, which was not apparent in Control Clubs. The health promotion message is pervading into many aspects of the GAA club apart from that which relates to the day to day business of coaching and providing physical activity for all. The HCP represents health promotion activity embedded within and across systems, with further development and evaluation recommended to measure delivery and impact at the individual level, organisational, and wider societal levels.