. The G0 project is a parity violation experiment dedicated to the measurement of the proton weak and axial form factors by means of elastic electron scattering. Combining these weak form factors with the known electromagnetic ones makes possible the extraction of the contribution of strange quarks to the charge and magnetization distributions in the nucleon. After introducing the physics case, this paper describes the G0 apparatus and the measurements planned. An engineering run of this experiment took place recently ; first results are presented.