We investigate nuclear dynamics and the Nuclear Equation of State (NEoS) by a detailed study of heavy-ion collisions at intermediate energies. In particular, we explore the isospin transport phenomena, occurring during the collision between the projectile and target having different neutron-to-proton ratios (N/Z). Two phenomena are investigated: the isospin diffusion and the isospin migration. The former is related to the nucleon exchange process between the projectile and the target, the latter is related to the neutron migration towards the low density region in the neck formed at mid-rapidity. Both provide an important information on the density dependence of the symmetry energy term of the NEoS.