The adverse effects of ozone and other air pollutants on crop yields are well documented. This paper reports on an assessment of the benefits to agriculture arising from reductions in ambient ozone pollution. Estimates are derived using recent plant science data as input for a spatial equilibrium model of U.S. agriculture. Sensitivity of benefit estimates to biological and economic sources of uncertainty is also investigated. Results suggest that the benefits of a 25 percent reduction in ambient ozone are substantial, amounting to $@@‐@@1.7 billion. The robustness of these estimates varies across alternative assumptions concerning response data and export markets.