In the direct conversion of methane to methanol by partial oxidation, to date, the most promising experimental results have been reported for the homogeneous gas phase reaction, but with considerable variation in methanol selectivities. In addition, multiple steady states and oscillations have also been observed under certain process conditions. A range in conversion and selectivity has also been reported for the reaction models that have been developed thus far for the homogeneous gas phase reaction. The aim of this chapter is to obtain a workable quantitative numerical model. The only control parameters at the disposal of the experimentalist are the equivalence ratio of CH4/O2, the surface to volume ratio, the total pressure, the ambient temperature, and the residence time in a CSTR. A comprehensive kinetic scheme containing 20 chemical species is developed. In a continuation of this work, the thermokinetic modeling studies have been extended to include the effects of overall heat transfer coefficient, oxygen concentration in the feed, residence time on the discontinuity and its associated hysteresis, the methanol selectivity, and the occurrence of oscillations.