Gaia is the sixth cornerstone of the ESA Scientific Programme. Beginning 2006, the programme implementation phase was kicked off at Astrium Satellites. At summer 2010 all Critical Design Reviews of the modules have been passed successfully, which enables to give a good snapshot of the development progress. This presentation summarizes the history of the satellite programme. The status of the current development will be presented with a focus of the main challenging equipment, with a particular insight on the payload.