NOVELTY - A hydrogen generator (10) has a hydrogen membrane reactor (12) (HR) with a combustion chamber (CC) and a reaction chamber (RC). A fuel supply line (20) transports fuel to RC. An oxygen supply line (22) transports oxygen to CC. A tail gas supply line (23) transports tail gases from RC. A line (24) transports combustion by-products from CC. A reaction product line (26) transports hydrogen from RC.    USE - For generation of hydrogen from ammonia or hydrocarbon fuels such as methanol, propane, butane and kerosene fuels (claimed).    ADVANTAGE - The hydrogen generator incorporates relatively small, efficient, hydrogen membrane reactor having excellent heat and mass transfer rates, and adapted to operate at relatively low reaction temperatures. The reaction chamber and the combustion chamber are incorporated with highly active catalyst having rapid residence time and excellent heat transfer ability. The hydrogen reactor is small and compact, and incorporates hydrogen reactor membranes capable of generating large volume of hydrogen. The hydrogen membrane allows hydrogen to diffuse across the membrane, and eliminates the need for further separation steps to obtain relatively pure hydrogen stream.    DETAILED DESCRIPTION - A hydrogen generator (10) has a hydrogen membrane reactor (12). The reactor (12) has a combustion chamber (CC) in a fluid connection and with heat exchange relationship with a reaction chamber (RC) . A fuel supply line (20) transports the fuel from a fuel supply (14) to RC. An oxygen supply line (22) transports oxygen from an oxygen supply (16) to CC. A tail gas supply line (23) transports tail gases from RC. A combustion by-product line (24) transports combustion by-products from CC. A reaction product line (26) transports hydrogen from RC.    An INDEPENDENT CLAIM is included for a method for generating hydrogen. A hydrogen-producing fuel flows through a reaction zone and into a combustion chamber of a hydrogen membrane reactor. The combustion chamber is in fluid connection with and in a heat exchange relationship with a reaction chamber. The reaction chamber includes a reaction zone and a reaction catalyst initially at a temperature less than the reaction catalyst's light-off temperature. The reaction zone separated from a hydrogen exhaust zone by a hydrogen separation membrane. The hydrogen-producing fuel is combusted to combustion by-products. While raising the temperature of the reaction catalyst in the reaction zone, the by-products are exhausted.    DESCRIPTION OF DRAWING(S) - The figure shows the block diagram of the primary components of the hydrogen generator.    Hydrogen generator (10)    Hydrogen membrane reactor (12)    Fuel supply (14)    Oxygen supply (16)    Fuel supply line (20)    Oxygen supply line (22)    Tail gas supply line (23)    Combustion by-product supply line (24)    Reaction product supply line (26)