Several processes for synthesis gas production are discussed: steam- and CO2-reforming, partial oxidation and autothermal reforming. Detailed kinetics are required for the successful simulation of these processes. Kinetic equations for steam- and CO2-reforming were developed based upon elementary steps between adsorbed species. Since the reactions are very fast, severe diffusion limitations occur. These were experimentally determined. The thresholds for carbon formation according to methane cracking and the Boudouard reaction were determined in an electrobalance reactor. Tubular reactors for steam- and CO2-reforming were modeled based upon a one-dimensional heterogeneous model accounting for internal diffusion limitations. In these simulations the heat fluxes along the reactor were calculated from a detailed temperature distribution in the furnace by means of the program FURNACE. Tubular reactors for steam- and CO2-reforming were also simulated based upon a two-dimensional model accounting for both radial and axial concentration gradients, leading to more accurate bounds for carbon deposition.