According to the Statutes of the IUCN,
States shall be those which are Members of the United Nations or any of its Specialized Agencies, or of the International Atomic Energy Agency, or parties to the Statute of the International Court of Justice. [IUCN Statutes, Article 5 (a)]
Government agencies shall be organisations, institutions and, when applicable, government departments, which form part of the
machinery of government in a State, including those agencies of the components of federal States or of States having an analogous structure; [IUCN Statutes, Article 5 (b)]
Political and/or economic integration organisations
Political and/or economic integration organisations shall be
organisations constituted solely by States to which those States have conferred legal competence in respect of matters within the objectives of IUCN. [IUCN Statutes, Article 5 (c)]
National non-governmental organisations (NGO)
National non-governmental organisations shall be institutions and
associations incorporated within a State. [IUCN Statutes, Article 5 (d)]
International non-governmental organisations (INGO)
International non-governmental organisations shall be institutions and associations organized in two or more States. [IUCN Statutes, Article 5 (e)]
Indigenous peoples’ organisations
Indigenous peoples’ organisations shall be institutions and associations established by indigenous peoples for the advancement of indigenous communities. [IUCN Statutes, Article 5 (f)]
States or political and/or economic integration organisations shall become Members of IUCN by notifying the Director General of their adhesion to these Statutes, effective upon payment of the first year’s membership dues.
Government agencies, national and international non-governmental organisations, indigenous peoples’ organisations and affiliates shall become Members of IUCN when the Council has determined that:
a) The applicant shares and supports the objectives of IUCN;
b) The applicant has as one of its central purposes the achievement of IUCN’s objectives and a substantial record of activity in the conservation of nature and natural resources;
c) The objectives and track record of the applicant embody to a
i) The conservation of the integrity and diversity of nature; and, either or both:
ii) The aim to ensure that any use of natural resources is equitable and ecologically sustainable;
iii) Dedication to influencing, encouraging and assisting societies to meet the objectives of IUCN;
d) The applicant does not pursue objectives or carry out activities that conflict with the objectives or activities of IUCN.
Information on the process to follow is available at How to become a Member of IUCN?