Abstract: A nitriding process and nitriding furnace therefor wherein the parts to be treated are maintained at floating potentional in a vacuum furnace (9), current being provided to a metal screen (5) cathode surrounding the parts to be treated, the necessary heat being provided by radiation from screen (5) whereby nitriding gas is injected into the furnace such that it has to flow through screen (5) where the plasma necessary for the nitriding reaction is generated by glow discharge the plasma flowing around and reacting with the parts to be treated before it is evacuated at the bottom of furnace (9) through vacuum/exhaust conduit (2).