The background and current status of the Environmental Lead Proficiency Analytical Testing (ELPAT) program were discussed. ELPAT is a collaborative project of the American Industrial Hygiene Association (AIHA), the Centers for Disease Control and Prevention, NIOSH, and the Environmental Protection Agency, administered by AIHA, designed to evaluate and improve the analytical performance of laboratories performing lead (7439921) analyses associated with lead abatement. Proficiency test samples are prepared by the Research Triangle Institute (RTI) using real world samples such as paint chips, dusts, and soils. Samples are sent each calendar quarter (designated a round) by RTI to participating laboratories. The proficiency evaluation involves comparing the results reported by the participating laboratories against an acceptable performance range, which has been derived from consensus values obtained at reference laboratories. Proficiency ratings are based on the performance of participating laboratories in the program over the preceding year (four rounds). A laboratory is judged to be proficient for a given lead matrix if all the results for all four rounds have been reported and are designated as acceptable for the last two consecutive rounds or 75% of the results reported in the last four rounds are judged to be acceptable. A total of 286 laboratories participated in the last completed round, round 6, February 1994. The participating laboratories used flame and graphite fusion atomic absorption spectrometry, individually coupled plasma/atomic emission spectrometry, X-ray fluorescence spectroscopy, and inductively coupled plasma/mass spectrometry for the analyses. The proportion of analyses judged to be acceptably performed by sample matrix was: paint chips, 91%; soil, 90%; and dust wipes, 94%.