The Clinical Laboratory Improvement Amendments (CLIA) are U.S. federal regulations that set standards for laboratory testing. Established in 1988, CLIA aims to ensure the accuracy, reliability, and timeliness of laboratory results. It applies to all clinical laboratories, including those performing tests for hospitals, physicians, and research facilities. CLIA categorizes laboratory tests into three main groups: waived, moderate complexity, and high complexity. Each category has specific requirements for quality control, personnel qualifications, and proficiency testing. By enforcing these standards, CLIA helps protect patients by ensuring that laboratory tests are performed safely and effectively.