The Alliance of Girls' Schools Australasia Ltd. was formed to promote the education of girls in single-sex girls' schools, and promote the image of, and support the development of, girls' schools in Australasia.
The Alliance's first AGM was held in May 1996, where membership of the Alliance was extended to all girls' schools in Australia and New Zealand whether independent, government or Catholic. The Alliance was incorporated 18 August 1997.
The alliance currently accepts membership from any school in Australia, New Zealand, Singapore, Hong Kong, the Philippines, and South Africa which is educating girls only.
It is affiliated with the Girls' Schools Association (GSA, UK) and the National Coalition of Girls' Schools (NCGS, US).
In 2013, the Alliance comprised 145 schools: