The concept implies that all contractors, fabricators and material manufactures involved must prove that the quality control system used, fulfills particular requirements at all manufacturing, inspection and testing stages. These requirements are laid down in two standards issued by the U. S. Atomic Energy Commission and the American Society of Mechanical Engineers. These standards are discussed in the paper. As a manufacturer of steel products for nuclear applications Sandvik has been forced to establish a quality assurance system according to these principles. The Sandvik approach is briefly described with regard to organization and other major quality assurance activities. Further education and training of operators and technicians is touched upon. Some viewpoints regarding audits performed by customers of steel manufacturers are expressed.