By their very nature, geodetic and geophysical studies require a high degree of international co-operation as well as effective central co-ordination. IUGG is fortunate in having 74 Member Adhering Bodies. The Members are distributed throughout the world.

The great majority of Member Adhering Bodies participate through IUGG National Committees set up by the national academy or another body in their country that adheres to the Union (though other methods of adherence do occur). Each IUGG National Committee is represented at the IUGG General Assemblies by a Delegate appointed by its Adhering Body.

Any multi-national or regional geodetic, geophysical or other geosciences organization can apply for Affiliate Membership of the Union. Affiliate Members shall have the same rights, duties and obligations as Associate Members. Detailed information about the IUGG Members can be found in the IUGG Yearbook.

Regional distribution of current (dark green) and former (light green) IUGG Member Countries (as of 01.01.2025)

National and Affiliate Members of IUGG