The GLAST mission belongs to the next generation of Gamma Ray Space Telescopes aiming at detecting photons from astrophysical sources in the energy range of a few keV up to > 300 GeV. The satellite will host two detectors: the Gamma ray Burst Monitor (GBM) and the Large Area Telescope (LAT). In this talk we will review the physics capabilities of the Large Area Telescope and report on the current status of the project. Preliminary results from a recent flight of a single module in a high-altitude scientific balloon will also be shown.