The EAO (East Asian Observatory) is formed  by EACOA (East Asian Core Observatories Association) for the purpose of pursuing joint projects in astronomy within the East Asian region. In the era of very large scale astronomical instruments, East Asia will be competitive internationally by combining their funding resources, their technical expertise, and their manpower. The intention of EAO is to build and operate facilities, which will enhance and leverage existing and planned regional facilities. The intention of EAO is to raise funding and to build an observatory staff, separate from that of the EACOA institutions. As partners of the EAO, the EACOA institutes will help to establish the funding and to oversee the governance of EAO. The communities represented by the partners in EAO would have full access to all EAO facilities.

The EAO is chartered as a non-profit Hawaii corporation. It is tasked to operate the James Clerk Maxwell Submillimetre Telescope (JCMT) on the summit of Maunakea, Hawai`i.