National Adhering Organizations (NAOs) are the formal Members of the Union, which represent the chemists in those countries. An Adhering Organization may be a national chemical council, a national society representing chemistry, a national academy of science, or any other institution or association of institutions representative of national chemical interests. Associate National Adhering Organizations have 'observer' status.

Associated Organizations are international organizations that share common goals and interests with IUPAC.

Company Associates are organizations such as industrial companies, research and development institutions and laboratories, or scientific societies, that are interested in IUPAC activities.

• National Adhering Organizations
• Associate National Adhering Organizations
• Associated Organizations
• Company Associates