ISASA requires independent schools applying for membership to undergo an initial quality assurance process to ensure that a potential member school meets the prescribed conditions for membership, provides quality education and is committed to adhere to principles of ethical practice.
Once a school is accepted for ISASA membership, it must undergo a regular quality assurance process every six years. This is undertaken by an independent organisation. Beginning in 2022, this organisation is the Office of Independent Schools Evaluations, Southern Africa (OISESA).