The background of the Environmental Lead Proficiency Analytical Testing (ELPAT) Program was described and its current status was discussed. The program was administered by the American Industrial Hygiene Association (AIHA) with the goal of evaluating and improving the performance of laboratories conducting analyses associated with lead (7439921) abatement. Test samples of paint, soil and dust were sent quarterly to participating laboratories and the performance of the laboratories was evaluated. Criteria for performance evaluation of the individual laboratories in the program were described, and results from testing were discussed. Round 17 took place in November 1996, with 364 laboratories submitting results. The percentages of all participating laboratory analyses that were identified as outliers was 6.4 to 7.8% for paint chips, 4.5 to 8.4% for soils, and 3.3 to 4.6% for dust wipes, similar to the frequency of outliers reported on earlier rounds of ELPAT for each matrix. No statistically significant differences in the ability of methods to measure lead used by participating laboratories were detected for paint chips, soils, or dust wipes. Bias differences among analytical methods were detected in the sample preparation techniques category. Round 18 samples were sent to participants on February 3, 1997.