This study used a static, partial budgeting approach to estimate the potential net benefits of the adoption of herbicide-tolerant transgenic rice in California. Scenarios were developed based on average cost figures across the state using actual pesticide use data and assuming a rice-only rotation, as well as a three-year field study of efficacy of herbicide regimes in the presence of herbicide-resistant watergrass. Results suggest that a management strategy including transgenic varieties could lead to economic benefits for the grower, as well as benefit the environment, given that conventional rice production in California involves heavy use of chemicals. Copyright 2003 by Bond, Carter, and Farzin. All rights reserved. Readers may make verbatim copies of this document for non-commercial purposes by any means, provided that this copyright notice appears on all such copies.