This final rule revises regulations applicable to laboratories and implements provisions of the Clinical Laboratory Improvement Amendments of 1988 (CLIA), Public Law 100-578. The regulation applies to laboratories that examine human specimens for the diagnosis, prevention, or treatment of any disease or impairment of, or the assessment of the health of, human beings. They specify the performance requirements, based on 19 test complexity and risk factors related to erroneous test results, that apply to laboratories that are subject to CLIA. They also list requirements for laboratories performing certain limited testing to be eligible for a certificate of waiver. These laboratories will not be inspected routinely, nor will they be required to meet certain other CLIA requirements.