The results of the Proficiency Analytical Testing Program (PAT) Round 120 were reported. The PAT Program, administered by the American Industrial Hygiene Association and the NIOSH, has provided quality assurance of occupational health and environmental laboratories in 18 countries by the analysis of samples sent each calendar quarter to participating laboratories and comparison of reported results with acceptable performance limits. In the current PAT Round, laboratories were requested to analyze methanol (67561) on silica-gel tube for the first time, in addition to various items in the metals, silica (14808607), asbestos (1332214), and organic solvents categories. Of the 1305 laboratories submitting results, 92.7% were found to be overall proficient. The relative standard deviations reported by PAT reference laboratories were approximately 2% higher than those reported for other organic solvents in the program. The number of analyses determined to be outliers was lower than the average number reported for other organic solvents. Compared with the typical number of laboratories participating in a given round about 15 fewer laboratories analyzed and reported the methanol results. A description of PAT Round 121, sent to participating laboratories on April 3, 1995, was presented.