Abstract Aluminum electrodeposition from aprotic solutions of the organic complex KF. 2Al(C 2H 5) 3 on polycrystalline aluminum and vitreous carbon is described for potentiostatic and voltage pulse conditions. Near the equilibrium of the aluminum electrode, below curents of about −3 mA cm −2, electron transfer controls the deposition rate. Stationary polarizations over −0.1 V generate a material transport limitation which was controlled and eliminated by the rotating disk electrode technique. Extending the overvoltage to −0.1 to −0.3 V a slow chemical process characterized by a reaction current of ca −5 mA cm −2 precedes charge transfer. Above −0.3 and −0.7 V two further deposition mechanisms possibly involving slow chemical and crystallization steps were observed. On a foreign substrate, ie vitreous carbon, it was found that peripheral kinetically controlled growth of instantaneously formed two-dimensional plates takes place on top of plates so as to produce three-dimensional nuclei which then grow by a transport limited mechanism.