A series of experiments has been conducted to characterize the kinetics of lithium reactions with mixtures of oxygen, nitrogen and steam. Lithium reaction rates with the various gas mixtures were determined as functions of the lithium temperature and the gas composition. In each experiment, gas of a desired composition was passed over lithium preheated to a specific temperature (between 400 and 900°C). It was found that the oxygen inhibited the nitrogen reaction rate by reacting much more quickly and keeping the nitrogen from the available lithium. Tests with steam and nitrogen indicate that the lithium-nitrogen reaction is catalyzed by the presence of steam and that little elemental hydrogen is generated.