Summary: Certification guidance issued by the Office of Child Support Enforcement addresses the system requirements of the Family Support Act of 1998 and the Department of Health and Human Service's implementing regulations. GAO found that the Office has administered the certification process consistently across states since it began certifying child support enforcement systems in 1993. It has used the same guidance for certification reviews and done reviews that were similar in scope and length for each level of certification. Although the Office published many certification reports on the results of its certification reviews, its reporting was not always consistent. For example, six preliminary certification review reports inaccurately described the criteria against which the systems' financial components were measured. As of March 1998, the Office had either certified or conditionally certified 25 of the 54 child support enforcement systems. The Office did 13 additional reviews and was preparing certification reports for those systems.