Based on authority granted by provisions of the Clean Air Act (42 U.S.C 7410, et seq.), the Quality Assurance Division of the Environmental Monitoring Systems Laboratory, Research Triangle Park, NC administers periodic surveys of analytical proficiency for sulfur dioxide, nitrogen dioxide, carbon monoxide, sulfate, nitrate, lead, and high-volume flow. Sample materials and devices that have been utilized during the 1980 surveys (performance audits) were developed to simulate collected air pollution samples as faithfully as possible. Integrity of the various sample materials is continuously monitored to ascertain stability, accuracy, uniformity, and representativeness of the pollutant concentrations. Since a major survey objective is the assessment of routine analytical performance, a brief evaluative report is promptly returned to each participant. A comprehensive report contains a summary of survey results for the year 1980.