- Abdus Salam International Centre for Theoretical Physics [Trieste]
- Aerospatiale Inc.
- Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail
- Agence Spatiale Européenne = European Space Agency
- Agenzia Spaziale Italiana
- AgroParisTech
- Air Force Research Laboratory
- Aix Marseille Université
- ALCATEL
- Alcatel R&D
- Alcatel Space Industries Toulouse (FRANCE)
- Alfven Laboratory
- Analytical Services and Materials, Inc.
- Angström Laboratory
- AP-HP - Hôpital Antoine Béclère [Clamart]
- Applied Marine Physics [Miami]
- Applied Physics Laboratory [Seattle]
- ARCHEORIENT - Environnements et sociétés de l'Orient ancien
- Arctic Geophysics Research
- Arecibo Observatory, National Astronomy and Ionosphere Center
- Argelander-Institut für Astronomie
- Argentière
- Argumentation, Décision, Raisonnement, Incertitude et Apprentissage
- Aristotle University of Thessaloniki
- Arts et Métiers Paristech ENSAM Aix-en-Provence
- Arts et Métiers Sciences et Technologies
- Assistance Publique - Hôpitaux de Marseille
- Assistance publique - Hôpitaux de Paris (AP-HP)
- Association of Universities for Research in Astronomy
- Astronomy Unit [London]
- Atmospheric Physics Laboratory [UCL London]
- Augsburg University [Augsburg College] [Minneapolis, MN, USA]
- Australia Telescope National Facility
- Austrian Academy of Sciences
- Austrian Federal Ministry of Economics and Labour
- Austrian Federal Office for Metrology and Surveying
- Austrian Research Centre Seibersdorf
- Automatic Control & Systems Engineering
- Avant création Cerema
- Avignon Université