This chapter discusses the development of stainless steel. It begins with some information on the discovery of stainless steel. This is followed by a discussion on the most important patents issued for stainless steel. Applications of stainless steel beyond their original use in cutlery and tableware are then presented. Information on the development of alloys for specific applications and on the argon oxygen decarburization process is also provided. The chapter ends with a discussion on the major use for stainless steel after WWII.