The oxidative dimerisation reaction of N,N-dimethyl-p-toluidine (DMT) in acetonitrile was studied by cyclic voltammetry using a range of concentrations from 1 to 70 mM at microdisk electrodes of radii 10, 12.5, and 50 mum using scan rates from 20 mV s(-1) to 6 V s(-1). Theory was developed to simulate the following mechanism using the ADI method and comparison made to experimental voltammograms. [GRPAHICS] The mechanism was found to be consistent with the observed data under all experimental conditions employed. The following rate constants were inferred: k(1) = (5.9 2.2) x 10(5) cm(3) mol(-1) s(-1), k(-1) approximate to 0, and k(2) = (9.2 +/- 3.8) x 10(8) cm(3) mol(-1) s(-1).