Summary: Federal agencies may use certification requirements to help ensure quality in the goods and services they buy. For example, before buying computer or electrical equipment, an agency may require that prospective sellers obtain a certification from Underwriters Laboratories or another organization that the product is safe. Similarly, an agency may also require that certain professionals meet specific educational standards or be approved as competent by a specific group before providing a service. This report describes (1) the extent and the variety of certification activities in the federal government; (2) the extent to which there are policies, procedures, or guidance governing those activities, either governmentwide or within selected agencies; and (3) an agency's certification procedures that could serve as an example or "best practice" for other agencies. GAO summarized this report in testimony before Congress; see: Certification Requirements: Guidance Governing Agency Actions Is Limited, by L. Nye Stevens, Director of Federal Management and Workforce Issues, before the Subcommittee on Benefits, House Committee on Veterans' Affairs. GAO/T-GGD-99-166, Sept. 9 (seven pages).