A hydrogen production method and facility in which a synthesis gas stream produced by the gasification of a carbonaceous substance is processed within a synthesis gas processing unit in which the carbon monoxide content is reacted with steam to produce additional hydrogen that is removed by a pressure swing adsorption unit. The tail gas from the pressure swing adsorption unit is further reformed with the addition of a hydrocarbon containing stream in a steam methane reforming system, further shifted to produce further additional hydrogen. The further hydrogen is then separated in another pressure swing adsorption unit.