At first we briefly introduce the backstepping method for stabilization issues. This method allows us to change (in some sense) the spectral of the linear operator and to get rapid stabilization of the KdV equation. Then we prove a Lebeau-Robbiano type bound which together with the backstepping lead to the controllability result. B eyond null controllability we will see that this approach is related to lost of derivative problems and small time stabilization problems.