Mechanical effects induced by ultrasonication can be very helpful for the activation of electrochemical reactions. The continuous cleaning of the electrodes by ultrasound irradiation of the electrochemical cell or the enhancement of mass transfer at the electrodes are examples of such activation. Finally, ultrasonication can play an important part for the orientation of reactions whose selectivities are very sensitive to stirring. Two very different examples have been chosen to illustrate these phenomena: the indirect electrooxidation of di-ketone-L-sorbose into the corresponding ketogulonic acid and the direct electroreduction of acetophenone into pinacol.