A compact integrated combustion reactor is described. In a preferred embodiment, the combustion catalyst is disposed in a staggered configuration such that the hot spot in an adjacent endothermic reaction chamber is substantially less than would occur with a conventional, unstaggered configuration. The integrated reactor may also include a methanation chamber for methanation of a reformate product. Systems containing reactant and product streams, and methods of conducting integrated combustion reactions are also described. A staggered catalyst conformation can be used more broadly for thermal chemical reactions requiring heat transfer in a layered device.