As the popularity of sport continues to grow, more community developers, planners, and leaders are recognizing the ability for sport to foster community. Similar to other community contexts, understanding the structure and management of sport remains central to community building. Therefore, the aim of this study is to explain how sport system structural variations affect the sense of community experienced by those in and around sport. Eight focus groups were conducted with 39 sport participants from both formal and informal sport settings across 19 different sports. The results highlight the seven factors (administrative consideration, common interest, competition, equity in administrative decisions, leadership, social spaces, and voluntary action) that were particularly important in building a sense of community within two sport settings and how the factors are manifest within each of the structures. This research demonstrates the opportunities that sport holds for fostering community when designed and implemented appropriately. (Contains 2 figures and 2 tables.)