42 Members (excluding the associate or suspended members but including the countries represented on their behalf) [The rulers are not necessarily the representatives in the organisation. ] :
| | ALBANIA | (Tirana) | | President Ilir Meta | | |
| | AUSTRIA | (Vienna) | | President Alexander Van der Bellen | | |
| | AUSTRALIA | (Canberra) | | Sir Peter Cosgrove | | |
| | BOSNIA AND HERZEGOVINA | (Sarajevo) | | President Bakir Izetbegovich | | |
| | BELGIUM | (Brussels) | | King Philippe | | |
| | BULGARIA | (Sofia) | | President Rumen Radev | | |
| | BRAZIL | (Brasilia) | | President Michel Temer | | |
| | BELARUS | (Minsk) | | President Alexander Lukashenko | | |
| | CANADA | (Ottawa) | | Queen Elizabeth II | | |
| | SWITZERLAND | (Berne lq + Lausanne j) | | President Alain Berset | | |
| | CZECHIA | (Prague elr + Brno dj + Lany r) | | President Milos Zeman | | |
| | GERMANY | (Berlin ar + Bonn lr + Karlsruhe d) | | Bundespresident Frank-Walter Steinmeier | | |
| | DENMARK | (Copenhagen) | | Queen Margaret II | | |
| | EUROPE | (Strasbourg) | | SG Thorbjorn Jagland (no) | | |
| | ESTONIA | (Tallinn a + Tartu b) | | President Kersti Kaljulaid | | |
| | SPAIN | (Madrid) | | King Philip VI | | |
| | FINLAND | (Helsinki a + Kultaranta s) | | President Sauli Niinisto | | |
| | FRANCE | (Paris) | | President Emmanuel Macron | | |
| | CROATIA | (Zagreb) | | President Kolinda Grabar-Kitarovich | | |
| | IRELAND | (Dublin) | | President Michael Daniel Higgins | | |
| | ISRAEL | (Jerusalem aru + Tel Aviv-Jaffa i) | | President Reuven Rivlin | | |
| | INDIA | (New Delhi a + Simla s + Bolarum w) | | President Ram Nath Kovind | | |
| | ITALY | (Rome a) | | President Sergio Mattarella | | |
| | LITHUANIA | (Vilnius) | | President Dalia Grybauskaite | | |
| | LATVIA | (Riga) | | President Raimonds Vejonis | | |
| | MOLDOVA | (Chisinau) | | President Igor Dodon | | |
| | MACEDONIA | (Skopje) | | President Gjorge Ivanov | | |
| | MEXICO | (Mexico City) | | President Enrique Pena Nieto | | |
| | NETHERLANDS | (Amsterdam a + The Hague jlr + Wassenaar r) | | King Willem-Alexander | | |
| | NORWAY | (Oslo) | | King Harald V | | |
| | POLAND | (Warsaw a) | | President Andrzej Duda | | |
| | ROMANIA | (Bucharest) | | President Klaus Iohannis | | |
| | SERBIA | (Belgrade) | | President Alexandar Vuchich | | |
| | RUSSIA | (Moscow a + Saint Petersburg d) | | President Vladimir Putin | | |
| | SWEDEN | (Stockholm) | | King Charles XVI Gustav | | |
| | SLOVENIA | (Ljubljana) | | President Borut Pahor | | |
| | SLOVAKIA | (Bratislava a + Kosice d) | | President Andrej Kiska | | |
| | TURKEY | (Ankara a) | | President Recep Tayyip Erdogan | | |
| | UKRAINE | (Kiev) | | President Petro Poroshenko | | |
| | UNITED KINGDOM | (London a + Westminster lr + Edinburgh s + Windsor r) | | Queen Elizabeth II | | |
| | AMERICA | (Washington-District of Columbia) | | President Donald Trump | | |
| | KOSOVO | (Prishtina) | | President Hashim Thaci | | |