TEPSA is a decentralised think tank that consists of members and associate members. Established in 1974 by four institutes, TEPSA has ever since increased its membership to include institutes throughout Europe following the enlargement rounds of the European Union. The members of TEPSA are leading national think tanks or research institutes in the field of European affairs. The network includes one member in each European Union member state but also institutes in European countries outside the EU. TEPSA also has associated members. Associated members are research institutes or associations focused on European affairs but not directly linked to an EU member state, for example due to their transnational nature.
TEPSA currently consists of 39 member institutes and associate members located in 35 European countries. TEPSA continues to expand its membership via a careful selection procedure. The TEPSA Board is the main organ in charge of the selection process, while it is the TEPSA General Assembly that holds the final decision-making powers. Institutes or associations interested in TEPSA membership or associated membership can contact the TEPSA Secretariat for more information.