Membership in the IAU is open to countries and individuals. The procedures for submission and approval of membership applications in the two categories are described in Chapter II of the Working Rules.
A brief summary of the procedures is given below. Deadlines for proposals to be considered at the IAU General Assembly in August 2000 are listed here.
An organisation representing a country which considers applying for Full or Associate Membership of the IAU (normally an Academy of Science or equivalent; see the Working Rules for details) should write to the General Secretary at the IAU Secretariat, preferably at least 18 months in advance of a General Assembly. Annual dues to the Union are paid by Member Countries as a number of Units of Contribution defined by the Category of Adherence of each country; Associate Member countries pay one-half Unit of Contribution annually. The approved Units of Contribution are 2950 CHF (Swiss Francs) for the year 1999 and 3040 CHF for the year 2000. Contributions beyond 2000 will be fixed by the 24th General Assembly in August 2000.
As a rule, Individual Membership in the IAU is open to scientists who have a Ph.D. or equivalent in some branch of astronomy and has a proven record of independent research (a few publications) during some years after the Ph.D. Individual members of the IAU do not pay dues to the Union. Normally, individual members are admitted on the proposal of the Adhering Body of their home country. Accordingly, applications for membership by individual astronomers should be addressed to the appropriate National Committee (not necessarily identical to the official Adhering Body) in the country of their nationality or long-term residence. Individual Membership for scientifically qualified individuals is, however, not limited to candidates residing in countries which are currently Full or Associate Members of the IAU. Application forms listing the personal information required for applications to be in order can be obtained from the National Committees or, in exceptional cases, by individual request to the Secretariat.
In all cases, the Secretariat can be contacted for further information.