Abstract: A steam reformer with internal hydrogen purification includes internal bulk hydrogen purification, internal hydrogen polishing to remove trace levels of carbon monoxide and carbon dioxide, an integrated combustion method utilizing waste gas to heat the reformer, efficient integration of heat transfer, and a compact design. One steam reformer shown includes a concentric cylindrical architecture nesting an annular combustion region, an annular reforming region, an annular hydrogen transport region, and a cylindrical polishing region. Other reformers shown include modified combustion systems distributed within a reformation region, isolated vaporization chambers, combustion systems providing uniform temperature gradient, and plate membrane construction methods.