The report examines process alternatives for the optimal use of natural gas and biomass for production of fuel-cell vehicle (FCV) fuel, emphasizing maximum displacement of petroleum and maximum reduction of overall fuel-cycle carbon oxide (CO2) emissions at least cost. Three routes are evaluated: (1) production of methanol from biomass and from natural gas by independent processes, (2) production of methanol or hydrogen by hydrogasification of biomass using natural gas as co-feedstock supplemented with, and without, the use of carbonaceous municipal wastes as co-feedstocks, and (3) production of methanol or hydrogen by addition of natural gas to a biomass-to-methanol process originally designed for biomass only. The results show that the combined use of natural gas and biomass in a single process can reduce net fuel-cycle CO2 emissions by 20% relative to separate systems and reduce the cost of fuel production to a range competitive with the current cost of gasoline.