LISA mission is planed to detect signals from different gravitational radiation sources such as the merger of black holes at the centers of galaxies or the capture of smaller objects by black holes. These signals will provide information on various unanswered questions: the birth and history of galaxies and massive black holes, the behavior of general relativity and space-time in its extreme limit, the history of the expansion of the Universe, the physics of dense matter and stellar remnants, and possibly a new feature of the early universe physics or string theory. LISA Pathfinder is the precursor space mission that will test the technology needed . In this talk we will comment on this mission and on the launch of LISA Pathfinder scheduled for December 2th at 5:15 CET.