AGBIS supports and advises governing bodies of schools in the independent sector on all aspects of governance, under the umbrella of the Independent Schools Council. The objectives of the Association are the advancement of education in independent schools and the promotion of good governance in such schools. The Association is empowered to give guidance to the governing bodies, and to consult with and speak for them on matters relating to the governance of independent schools.  This includes providing expert advice on governance, webinars, on-site training, seminars, events and reviews of governance as well as providing access to a range of template governance documents and policies.

AGBIS has in recent years welcomed a growing number of preparatory schools into membership and the number of governing bodies who benefit from membership steadily increases.