This information report presents a preliminary discussion of liquid propellant gas generation (LPGG) systems. A LPGG system@ as used herein@ is defined as a system which stores a liquid propellant and@ on command@ discharges and converts the liquid propellant to a gas. The LPGG system can interface with a gas-to-mechanical energy conversion device to make up an auxiliary power system. Figure 1 shows a block diagram of LPGG system components which include a propellant tank@ propellant expulsion system@ propellant control and a decomposition (or combustion) chamber. The purpose of this report is to provide general information on the variety of components and system arrangements which can be considered in LPGG design@ summarize advantages and disadvantages of various approaches and provide basic sizing methods suitable for initial tradeoff purposes.