The membership of the Academy consists of:
- Academy Members
- Honorary Members (very rarely nominated)
- Corresponding Members
The specific criteria for electing, appointing, and recognizing the various classes of membership are fixed by the Bylaws.
Academicians shall be distinguished leaders in their fields who have made outstanding contributions to the development of astronautics, to international cooperation in the peaceful uses of outer space, or to the activities of the Academy.
Corresponding Members shall be recognized authorities and experts who have made contributions in their fields to the development of astronautics in their countries and are dedicated to furthering international cooperation in the aerospace sciences.
The rigorous admission process to the International Academy of Astronautics starts by first being nominated as Corresponding Member. The consideration of a candidate requires:
- a nomination by at least 3 Academicians and
- a nomination of non-members who have made outstanding contributions to the field of astronautics as demonstrated by:
- membership in their national academies of science or engineering;
- attainment of the highest grade in their professional organization; or
- other types of peer recognition shall also be eligible for nomination.
International nominations are welcomed. Consequently a nomination supported by three Academicians (Members) of the same nationality is rejected.