27 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. ] :
| | AUSTRIA | (Vienna) | | President Adolf Schaerf | | |
| | BELGIUM | (Brussels) | | King Baudoin I | | |
| | SWITZERLAND | (Berne lq + Lausanne j) | | President Max Petitpierre | | |
| | WEST GERMANY | (Bonn ar + Karlsruhe d) | | Bundespresident Heinrich Luebke | | |
| | DENMARK | (Copenhagen) | | King Frederick IX | | |
| | UNITED ARAB | (Cairo a + Alexandria r) | | President Gamal Abdel Nasser | | |
| | SPAIN | (Madrid) | | Caudillo Francisco Franco | | |
| | FRANCE | (Paris) | | President Charles de Gaulle | | |
| | GREECE | (Athens a) | | King Paul I | | |
| | HAITI | (Port Au Prince) | | President Francois Duvalier Papa Doc | | |
| | INDONESIA | (Jakarta a + Bogor r + Chipanas r + Jogjakarta r + Tampaksiring r) | | President Ahmad Sukarno | | |
| | IRELAND | (Dublin) | | President Eamon de Valera | | |
| | ISRAEL | (West Jerusalem qu + Tel Aviv-Jaffa i) | | President Yitzhak Ben-Zvi | | |
| | IRAN | (Tehran) | | Mohammad Reza Shah Pahlavi | | |
| | ITALY | (Rome a) | | President Giovanni Gronchi | | |
| | LEBANON | (Beirut a + Baabda r) | | President Fuad Chehab | | |
| | LUXEMBOURG | (Luxembourg a) | | Grand Duchess Charlotte | | |
| | NETHERLANDS | (Amsterdam a + The Hague jlr + Wassenaar r) | | Queen Juliana | | |
| | NORWAY | (Oslo) | | King Olav V | | |
| | PAKISTAN | (Rawalpindi t + Karachi b) | | President Mohammad Ayub Khan | | |
| | PORTUGAL | (Lisbon) | | President Americo Thomaz | | |
| | SUDAN | (Khartoum) | | General Ibrahim Abboud | | |
| | SWEDEN | (Stockholm) | | King Gustav VI Adolphe | | |
| | NORTHERN REGION | (Damascus) | | | | |
| | TURKEY | (Ankara a) | | Cemal Gursel | | |
| | UNITED KINGDOM | (London a + Westminster lr + Edinburgh s + Windsor r) | | Queen Elizabeth II | | |
| | YUGOSLAVIA | (Belgrade) | | President Josip Broz Tito | | |