NOVELTY - Producing hydrogen gas from fuel involves utilizing autothermal primary reactor with first reforming reaction zone near inlet and second reforming reaction zone near outlet; utilizing at least one upstream reforming catalyst in first reforming reaction zone and at least one downstream catalyst in second reforming reaction zone; and passing reaction mixture of hydrocarbon fuel, oxygen and steam through reaction zones.    USE - Producing hydrogen-rich gas stream for powering fuel cells (claimed).    ADVANTAGE - The reforming catalyst has lower light-off temperature that allows primary reactor to be started with a lower amount of energy input thus providing fast light-off ability. The reforming catalysts with ceria and zirconia exhibit improved activity and ability to reform large concentrations of hydrocarbon fuel. The reforming catalysts with stabilizers enhance the thermal durability of the support and assist the support material in retaining porosity. The reforming catalysts with Group I, Group II, manganese or iron metal promoter have the ability to steam reform low concentrations of fuel and short chain hydrocarbons, respectively. As a result, hydrogen gas is produced more efficiently using reforming catalysts in the process.    DETAILED DESCRIPTION - Producing hydrogen gas from fuel involves:    (a) utilizing autothermal primary reactor with first reforming reaction zone near inlet and second reforming reaction zone near outlet;    (b) utilizing at least one upstream reforming catalyst in first reforming reaction zone and at least one downstream catalyst in second reforming reaction zone; and    (c) passing reaction mixture of hydrocarbon fuel, oxygen and steam through reaction zones.    Reformation reaction takes place in the reaction zones to produce product gases including hydrogen. The reforming catalyst has platinum group metals (e.g. rhodium or platinum) as catalysts on a support material. The support material in upstream reforming catalyst comprises an oxidic support and stabilizers (e.g. lanthanum and/or neodymium) or promoter comprising ceria and zirconia. The support material in downstream reforming catalysts has an oxidic support and at least one Group I, Group II, manganese or iron metal promoter. The first reforming reaction zone operates at a higher temperature and fuel concentration than that of second reforming reaction. The reforming catalysts are selected to perform in conjunction with operating conditions of their respective reaction zones.    INDEPENDENT CLAIMS are also included for the following:    (1) a fuel cell system with a fuel processing system producing hydrogen; and    (2) a vehicle with a fuel processing system producing hydrogen to provide motive power.