Early concepts of quality in clinical laboratory services stressed accuracy and precision. In the 1960s voluntary and mandated programs for laboratory accreditation followed. The increasing complexity of laboratory standard setting led to the promulgation of voluntary consensus standards in the 1970s. This was followed by a national reference system to minimize bias among clinical laboratories. The concept of total quality control emphasized that quality assurance must be a way of life for laboratorians, and concerns about growing laboratory volume led to the idea that managing laboratory utilization is also a component of quality assurance. Recent conferences have expanded the concept of laboratory quality to encompass everyone who participates, even remotely, in the provision of services. Now quality is evaluated by how well the patient is served.