G. Manzi, R. Marra A kinetic model of interface motion (65K, latex) ABSTRACT. We study a kinetic model for a system of two species of particles interacting via a repulsive long range potential and with a reservoir at fixed temperature. The interaction between the particles is modeled by a Vlasov term and the thermal bath by a Fokker-Plank term. We show that in the diffusive and sharp interface limit the motion of the interfaces at low temperature is described by a Stefan problem or a Mullins-Sekerka motion, depending on the time scale.