Abstract: X-Shooter is a second generation VLT instrument whose construction has been approved by ESO council in December 2003. It will be realised by a consortium formed by Institutes from four countries: Denmark, Italy, The Netherlands and France, and ESO. It is a wide-band single target spectrograph covering in a single exposure the spectral range from the U to K band (0.3-2.4 micron) with maximum sensitivity and intermediate resolution (R ~ 4000-10000). Gamma-ray Bursts and Type Ia Supernovae, along with their host galaxies, are among the main scientific objectives of X-Shooter. Thanks to its fast response, high efficiency and high sensitivity, X-Shooter will observe these rapidly varying objects with unprecedented precision. We will briefly discuss the main characteristics of X-Shooter, the French contribution to the project and the main scientific questions that will be investigated with this new instrument.