The results of round 13 of the Environmental Lead (7439921) Proficiency Analytical Testing (ELPAT) program were presented. ELPAT was a program administered by the American Industrial Hygiene Association (AIHA) in cooperation with NIOSH and the Office of Pollution Prevention and Toxics, Environmental Protection Agency (EPA) to evaluate and improve the performance of laboratories performing analyses associated with lead abatement. The program was part of the National Lead Laboratory Accreditation Project, an EPA sponsored program for accrediting private and state laboratories. Any interested laboratory could participate in the ELPAT program. Proficiency test samples for the participating laboratories were prepared by the Research Triangle Institute, an AIHA contractor, using paint chips, dust wipes, and soils. Four samples of each matrix were prepared. The samples were sent out each calendar quarter (round). Laboratories were rated based upon their performance in the ELPAT program over the past year (four rounds) for each lead matrix: paint chips, soil, and dust wipes. A laboratory was rated as proficient if all four sample results for each matrix were reported and designated acceptable for the last two consecutive rounds or at least 75% of the results reported in the last four consecutive rounds were judged acceptable. A total of 402 laboratories were enrolled for round 13, the samples for which were sent out in November 1995. A total of 371 (92%) laboratories submitted results. Flameless atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry were the major analytical methods used. Of the 366 laboratories that submitted results for the paint chip samples, 94% reported results judged to be acceptable. Of the 315 laboratories that submitted results for the soil samples, 95% reported acceptable results. Of the 340 laboratories that submitted results for the dust wipes, 95% reported acceptable results.