Under the Clean Air Act Amendments of 1977, the EPA is required to review and if appropriate revise the air quality criteria for the primary (health-based) and secondary (welfare-based) national ambient air quality standards (NAAQS) every five years. On November 12, 2008, the EPA published a final rule to revise the primary and secondary NAAQS for lead to provide increased protection for public health and welfare. The EPA has now initiated the next review. This new review includes the preparation of an Integrated Review Plan, an Integrated Science Assessment, and, if warranted, a Risk/Exposure Assessment, and also a Policy Assessment Document by the EPA, with opportunities for review by EPA's Clean Air Scientific Advisory Committee and the public. These documents inform the Administrator's proposed decision as to whether to retain or revise the standards. This decision will be published in the Federal Register with opportunity provided for public comment. The Administrator's final decisions will take into consideration these documents and public comment on the proposed decision.