Corrosion resistant steels - especially the austenitic and the ferritic-austenitic "duplex" grades - represent basic materials of construction for the chemical industry. They serve in cryogenic and high temperature applications, but are most often used in aggressive highly acid to alkaline, frequently aqueous media. The criteria for the selection of corrosion resistant steels are governed not only by the corrosion resistance requirements, but also may be dominated by product cleanline and other process requirements, The development and the market introduction of corrosion resistant steels is closely connected with developments in the chemical process industry. Service experience for corrosion resistant steels is reported, and critical failure mechanisms like pitting and stress corrosion cracking, and their avoidance by appropriate material selection, are mentioned.