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Nitrogen in low alloy steels is undesirable due to the formation of brittle nitrides. However, the use of nitrogen in high alloy steels has an array of advantages that makes it appear interesting as an alloying element. The effects of nitrogen addition as alloying element are mainly significant increase of strength without restricting ductility, improvement of corrosion resistance, increasing the high temperature tensile strength, extended / stabilized austenite form, no formation of tension induced martensite with high cold working rates, and inhibition of the discharge of inter-metallic phases. These HNS alloys (High Nitrogen Steels) specific material group are characterised through an interesting material profile, i.e a combination of strength and corrosion resistance. A state-of-the-art production routine is P-ESR melting (pressurised electro slag remelting) is covered within this paper. Austenitic steels as well as martensitic steels can be manufactured and are suitable for forging and hot rolling. Some basic knowledge about the material characteristics is mandatory to avoid any potential issues at plastic deformation, heat treatment and to maintain the excellent corrosion resistance. This paper provides an overview about the role of nitrogen related to corrosion of stainless steels. Since a lot of results have been published to date, common knowledge is summarized and topped up with own data and experimental results. Finally, some typical HNS grades are discussed with regards to their industrial application.