The CoRoT mission and its scientific objectives

The CoRoT project, developed in the framework of the CNES small satellite programme with a wide european cooperation, has been set up in the early nineties, and will be launched in december 2006. It is dedicated to seismology and detection of rocky planets. In both domains it is a precursor and a pathfinder. Though the programmatic framework imposes quite strong limitations, it is possible to perform both a seismology and an exoplanet finder programme of prime scientific interest.We recall here the scientific specifications, written first in 1998 and upgraded till 2002, which have driven the concept of the instrument and its realisation.The knowledge on ultra‐high precision photometry from space acquired in building CoRoT, and its scientific results, will certainly be very helpful in the definition and preparation of the next generation missions.