Quality has become the hallmark of industrial excellence. Many diverse factors have heightened national concern about managing quality control throughout the health-care industry, including laboratory services. Industry-wide focus on quality control has created a need for an administrative program to evaluate its effectiveness. That program is medical quality assurance. Because of national and industry-wide concern, development of quality assurance theory has gained increasing importance in medical accreditation and management circles. Scrutiny of the application of quality assurance has become particularly prominent during accreditation inspections. Implementing quality assurance programs now demands more of already finite resources. The professional laboratory manager should understand how quality assurance has developed in the United States during the past 150 years. The well-informed manager should recognize why the health-care industry only recently began to develop its own expertise in quality assurance. It is also worthwhile to understand how heavily health care has relied on the lessons learned in the non-health-care sector. This three-part series will present information that will help in applying quality assurance more effectively as a management tool in the medical laboratory. This first part outlines the early industrial, socioeconomic, and medicolegal background of quality assurance. Terminology is defined with some distinction made between the terms management and administration. The second part will address current accreditation requirements. Special emphasis will be placed on the practical application of accreditation guidelines, providing a template for quality assurance methods in the medical laboratory. The third part will provide an overview of quality assurance as a total management tool with some suggestions for developing and implementing a quality assurance program.