The association was formed in 1929 to provide sporting and co-curricular competition with the foundation members being the above schools with the exception of All Saints', who were not mentioned again.

CAS also offers a wide range of cultural activities such as cadet competitions, chess, debating and public speaking.

Sydney Grammar School often participates in debating competitions and some sport (mainly volleyball) hosted by the CAS board.

Tony Higgins, dean of careers at Knox Grammar School, manages the employment relations aspect of the association.

John Day and Roger Seaborn, members of the Trinity Grammar School Council, also form part of this committee and are responsible for the day-to-day operation of the CAS.

Awarded annually, the student attaining the scholarship is granted six years of secondary education at any of the six CAS schools.

The head of the CAS committee, Dougal Parr, also announced his decision to step down from his position and was replaced by his deputy, Edward Bradshaw.

Headed by the dean of English of Knox Grammar School and Barker College, Steve Parsons and Ann Lawless Bean, assessment tasks, examinations and teaching schedules were devised for the academic year commencing 2008.