A dual-zone steam fuser for a xerographic system includes a ultra-heated first zone maintained at 200-500.degree. C. that quickly heats a paper substrate to an optimal toner fusing temperature (e.g., 120-150.degree. C.), and a second, relatively cool second zone for maintaining the substrate at the optimal temperature during completion of the fusing process. A conveying system conveys the substrate so that it exits the first zone and enters the second zone immediately after the substrate temperature reaches the optimal toner fusing temperature, and is maintained in the second zone for a predetermined fusing operation time period. The gas (e.g., steam) temperatures and timing are selected such that surface condensation is minimized during initial heating, and such that moisture content is normalized at the end of the fusing process.