The Pleiades requirements were analysed by CNES with the help of the community of users. For this purpose, the main french players in the field of Earth Observation made their contribution, both as user organisations (IGN, BRGM, INRA, CNRS), or as services providers (like SPOT IMAGE, SCOT, ACRI).
The results and recommandations derived from forums with different communities of users, organised by the Ministry of Education, Research and Technology (MENRT) as part of the "Space & Society" meetings were also taken into account. Similarly, the needs of the European Commission in term of geospatial and environmental information, particularly those expressed by means of the GMES initiative, were also been taken into consideration.
The CNES analysis was confirmed by the analisys performed by ESA for the ERSIS study conducted by leading European industrialists and by that of the italian space agency (ASI), for its Cosmo-Skymed project.
Lastly, two seminars were organized by CNES in March and May 2000, to confirm the results obtained.
These analyses demonstrated the need for an optical and radar metric resolution observation system to detect, recognize and identify interesting targets or objects and their evolution. Italy and France decided in 2001 to join their effort to develop such a system named ORFEO (Optical and Radar Federated Earth Observation) through a governmental agreement signed in January 2001 in Turin.