This Staff Paper, prepared by staff in the U.S. Environmental Protection Agencys (EPA) Office of Air Quality Planning and Standards (OAQPS), evaluates the policy implications of the key studies and scientific information contained in the document, Air Quality Criteria for Ozone and Related Photochemical Oxidants (USEPA, 2006; henceforth referred to as the CD), prepared by EPAs National Center for Environmental Assessment (NCEA). This document also presents and interprets results from several quantitative analyses (e.g., air quality analyses, human exposure analyses, human health risk assessments, and an environmental assessment of vegetation-related impacts) that we believe should also be considered in EPA's current review of the national ambient air quality standards (NAAQS) for ozone (O(sub 3)), and presents factors relevant to the evaluation of current primary and secondary 03 standards. Finally, this document presents staff conclusions and recommendations on a range of policy options that we believe are appropriate for the Administrator to consider concerning whether, and if so how, to revise the primary (health-based) and secondary (welfare-based) O(sub 3) NAAQS.