An international seismological experiment aims at the crustal and upper mantle structure of the highly seismogenic Vrancea Zone in Romania. Refraction seismology will reveal crustal velocities and the Moho topography. Local and teleseismic tomography aim at upper mantle structures (velocities and attenuation) where the strong intermediate depth earthquake are located. The experiment will constrain earthquake hypocenters and their maximum magnitudes and thus directly contribute to hazard assessment.