The conferences and symposia listed below were organised by national or international bodies for which NEA co-sponsorship or co-operation was requested.
| 10‑14 January | 2004 North American Regional ISOE ALARA Symposium |
| Organiser | North American Technical Center (NATC) |
| Where | Miami, Florida, USA |
| 21‑25 March | PBNC 2004 – 14th Pacific Basin Nuclear Conference and Technology Exhibit – New Technologies for a New Era |
| Organiser | American Nuclear Society (ANS), conducted under the auspices of the Pacific Nuclear Council |
| Where | Honolulu, Hawaii, USA. |
| 25‑29 April | 12th International Conference on Nuclear Engineering (ICONE 12) |
| Organiser | American Society of Mechanical Engineers |
| Where | Arlington, Virginia (Washington, D.C.), USA |
| 25‑29 April | PHYSOR-2004 – The Physics of Fuel Cycles and Advanced Nuclear Systems: Global Developments |
| Organiser | Argonne National Laboratory (ANL) |
| Where | Hyatt Regency Chicago, Chicago, Illinois, USA |
| 26‑28 April | DisTech 2004 – Disposal Technologies and Concepts 2004: International Conference on Radioactive Waste Disposal |
| Organisers | Bundesamt für Strahlenschutz (BfS), Salzgitter, Germany; Deutsche Gesellschaft zum Bau und Betrieb von Endlagern für Abfallstoffe mbH (DBE), Peine, Germany |
| Where | Berlin, Germany |
| 2‑6 May | ANS International Topical Meeting on Advanced Nuclear Installation Safety |
| Organiser | American Nuclear Society (ANS) |
| Where | San Francisco, California, USA |
| 9‑13 May | IYNC 2004 – International Youth Nuclear Congress Youth, future, nuclear |
| Organiser | Canadian Nuclear Society |
| Where | Toronto, Canada |
| 9‑14 May | 10th International Conference on Radiation Shielding (ICRS-10), and 13th Topical Meeting on Radiation Protection and Shielding (RPS-2004) |
| Organiser | ITN in Lisbon (Nuclear and Technological Institute) |
| Where | Madeira, Portugal |
| 23‑28 May | IRPA 11 – 11th International Congress of the International Radiation Protection Association |
| Organiser | Spanish Radiological Protection Society (SEPR) |
| Where | Madrid, Spain |
| 13‑17 June | ICAPP 04 – ANS 2004 International Congress on Advances in Nuclear Power Plants |
| Organiser | American Nuclear Society (ANS) |
| Where | Pittsburgh, PA, USA |
| 14‑18 June | 7th International Conference on Probabilistic Safety Assessment and Management (PSAM 7 – ESREL 04) |
| Organisers | International Association for Probabilistic Safety Assessment and Management (IAPSAM) & European Safety and Reliability Association (ESRA) |
| Where | Berlin, Germany |
| 21‑24 June | ATALANTE 2004: Advances for future nuclear fuel cycles |
| Organiser | French Alternative Energies and Atomic Energy Commission (CEA) |
| Where | Nîmes, France |
| 22‑26 August | ANS Spectrum 2004: Closure of Nuclear Facilities |
| Organiser | American Nuclear Society (ANS), Fuel Cycle and Waste Management Division. Sponsors: Decommissioning, Decontamination & Reutilization Division, DOE Environmental Management, DOE Office of Civilian Radioactive Waste Management |
| Where | Atlanta, GA, USA |
| 29 August‑3 September | Sixth International Conference on Nuclear and Radiochemistry |
| Organiser | Forschungszentrum Jülich GmbH |
| Where | Aachen, Germany |
| 6‑10 September | Workshop on Safe, Efficient and Cost-Effective Decommissioning |
| Organiser | NEA in co-operation with the IAEA and EC; hosted by Società Gestione Impianti Nucleari (SOGIN) and the Italian Agency for Environment Protection and for Technical Services (APAT) |
| Where | Rome, Italy |
| 7‑10 September | International Conference on Nuclear Knowledge Management |
| Organiser | International Atomic Energy Agency (IAEA) Hosted by: Government of France through the French Alternative Energies and Atomic Energy Commission (CEA) |
| Where | Saclay, France |
| 19‑24 September | 2004 International Meeting on Light Water Reactor Fuel Performance |
| Organiser | American Nuclear Society (ANS) |
| Where | Orlando, Florida, USA |
| 26 September‑1 October | International Conference on Nuclear Data for Science and Technology (ND-2004) |
| Organiser | NEA, Los Alamos National Laboratory (LANL) |
| Where | Santa Fe, USA |
| 3‑6 October | Third International Conference on the Fatigue of Components and Structures |
| Organiser | NEA, Electric Power Research Institute (EPRI) |
| Where | Seville, Spain |
| 13‑17 December | IAEA International Symposium on the Disposal of Low-Activity Radioactive Waste |
| Organiser | International Atomic Energy Agency (IAEA) |
| Where | Cordoba, Spain |
