Elevated blood lead levels (BLLs) in adults can damage the cardiovascular, central nervous, reproductive, hematologic, and renal systems. The majority of cases are workplace-related. U.S. Department of Health and Human Services recommends that BLLs among all adults be reduced to <25 ug/dL. The highest BLL acceptable by standards of the U.S. Occupational Safety and Health Administration is 40 ug/dL. The mean BLL of adults in the United States is <3 ug/dL. This report covers cases of adults (aged > or equal to 16 years) with BLLs > or equal to 25 ug/dL, as reported by 25 states during 1998-2001. Since 1987, CDC has sponsored the state-based Adult Blood Lead Epidemiology and Surveillance (ABLES) program to track cases of elevated BLLs and provide intervention consultation and other assistance. Overall ABLES program data were last published in 1999 for the years 1994 - 1997. This report provides an update with data from 25 states reporting for > or equal to 2 years during 1998 - 2001. During that period, the ABLES program funded surveillance in 21 states - Alabama, Arizona, Connecticut, Iowa, Maryland, Massachusetts, Michigan, Minnesota, New Jersey, New York, North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, Texas, Washington, Wisconsin, and Wyoming. Four additional states - California, Nebraska, New Hampshire, and Utah - contributed data without CDC funding. During 1998--2001, the overall program's annual mean state prevalence rate for adults with BLLs > or equal to 25 ug/dL was 13.4/100,000 employed adults. This compares with 15.2/100,000 for 1994-1997. Yearly rates were 13.8 (1998), 12.9 (1999), 14.3 (2000), and 12.5 (2001). For adults with BLLs > or equal to 40 ug/dL, the overall program's annual mean state prevalence rate during 1998-2001 was 2.9/100,000 employed adults. This compares with 3.9/100,000 for 1994-1997. Yearly rates were 3.3 (1998), 2.5 (1999), 2.9 (2000), and 2.8 (2001). Although certain limitations exist, the overall ABLES data indicate a declining trend in elevated BLLs among employed adults. ABLES-funded states increased from 21 to 35 in 2002, and more detailed reporting requirements were put into effect. These, and other improvements, will enable the ABLES program to work more effectively toward its 2010 target of eliminating all cases of BLLs > or equal to 25 ug/dL in adults caused by workplace exposures.