The five-step mechanism proposed earlier for the formation of phospholipid films at aqueous/organic interfaces and for their behaviour involving transfer of protons from the aqueous to the organic phase was further studied by cyclic voltammetry. A theoretical model was created for this mechanism and compared with the experimental results. Both the experimental and theoretical results support the proposed mechanism and evaluate the importance of the individual steps. It seems that the decisive step is the regeneration of the zwitterionic form of the phospholipid at the interface, ensuring stability of the film in time and its continuous functioning. In view of the complexity of the system, a wider selection of methods will be needed for a further study of this system; the theoretical model will then gradually be made more sophisticated. (C) 2008 Published by Elsevier B.V.