Gaia is ESA's cornerstone mission to measure the positions and parallaxes of one billion stars with unprecedented accuracy. The Gaia mission will be launched very soon and first science data from the spacecraft are expected to be received by the end of 2013. This implies the handling and processing of several hundred million
of observations per day, every day for the mission duration of five years. After this initial daily processing, a highly sophisticated processing of all data will derive the final mission products,i.e., the Gaia catalog.
This data challenge is taken up by the Gaia Data Processing and Analysis Consortium (DPAC) which consists of over 400 scientists, distributed across Europe. This paper presents how DPAC is structured and how it foresees to conduct its operations to ultimately deliver the Gaia promise. Some lessons learned from the development phase, which will impact the operations, will be given as well to indicate some of the peculiarities faced in such a large science consortium.