Substituted indenes were chosen as model compounds for studying the electrochemical reduction of the carbon-carbon double bond with the aim to investigate the different mechanisms of decay of the anionic intermediates generated at the electrode (radical anions, dianions and monoanions) in relation to the structure of the substrate and the acidic character of the proton donor present in the medium. With the aid of different electrochemical techniques a comprehensive picture of the reduction process was attained. The results are reviewed and discussed with particular emphasis to electron and proton transfer processes, including self-protonation (father-son and grandfather-grandson reactions), rearrangements and stereochemistry.