The OBU's contributions span various realms, from financial assistance for School buildings and developments, to the provision of scholarships and bursaries. In addition to its tangible support, the Old Boys' Union plays a pivotal role in the School's governance. Through the election of five members to the School Council, it ensures the preservation of the institution's ethos and traditions.For younger members, participation in sports clubs such as the Old Boys' Rugby Club and Football Club, allows Old Boys to stay connected to the School whilst engaging in competitive sports against teams from across Sydney. The OBU's contributions span various realms, from financial assistance for School buildings and developments, to the provision of scholarships and bursaries.