The gas-phase chemical kinetics of diesel fuel ignition, without and with ignition-enhancing additives, have been studied. A kinetics chain mechanism was developed to analytically describe the ignition processes. The mechanism treats a surrogate diesel fuel mixture consisting of representative alkane, aromatic and naphthenic components. Wind tunnel experiments were conducted wherein premixed, prevaporized diesel fuel-air flames were stabilized in a model combustor for times measured in minutes, thereby permitting extensive emissions measurements to be made. Ignition delay times predicted by the analytical model were in good agreement with those deduced experimentally.