The suitable design and quality of systems, structures, and components important to safety is vital for the construction and operation of nuclear power plants. The IAEA has developed this publication to provide information on approaches to evaluating the suitability of commercial grade items for use in nuclear power plant safety systems. Nuclear power plants in long-term operation have greatly benefited from the use of commercial-grade products, while the near-term deployment of advanced reactor designs, including small modular reactors, is expected to leverage such products to a large extent. The intended audience ranges from nuclear power plant senior management to experts procuring and controlling products and services vital for safety.