The National Air Quality Forecast System (NAQFS), developed as a partnership between the Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA), was tested during the summer of 2003 in preparation for deploying an initial forecast capability by September of 2004 (see, http://www.nws.noaa.gov/ost/air_quality/index.htm). The goal of the NAQFS is to provide the United States with air quality forecasts with accuracy sufficient to allow the public to take action to prevent or reduce the adverse health effects of these pollutants. The key to attaining this goal is the development of a consistent and reliable national forecast system. As a first step, twice daily O3 forecasts from a numerical model developed by the EPA/NOAA partnership were issued during the summer of 2003. As part of the evaluation of this model, NOAA and EPA formed a partnership with a focus group of state and local air quality forecasters. This focus group provided daily feedback and evaluation of the accuracy of forecasted O3 concentrations in their forecast areas, assessments of the most effective means to improve forecast accuracy, and a variety of other suggestions for improving forecast guidance. This paper reports on the evaluation of the NAQFS by the forecasters focus group and, in particular, on the results of a two-day model evaluation workshop held in September of 2003. The views expressed are those of the authors and do not necessarily represent those of the National Weather Service.