Solutions of nitromethane in acetone which are too dilute to support a self‐sustained detonation can be forced to react by a strong booster. In such cases the wave front is composed of an induction zone followed by a turbulent reaction zone and a region of turbulence decay. As the nitromethane concentration is increased, the induction zone disappears and reaction appears to begin at the wave front. At the highest concentrations no wave structure could be resolved and the reaction time may be subnanosecond with the booster system used.