Technology Adoption and Technical Efficiency: Organic and Conventional Dairy Farms in the United States Carlos D. Mayen, Joseph V. Balagtas, and Corinne E. Alexander Abstract We compare productivity and technical efficiency of organic and conventional dairy farms in the United States. We address self-selection into organic farming by using propensity score matching and explicitly test the hypothesis that organic and conventional farms employ a single, homogeneous technology. Utilizing the 2005 Agricultural Resource Management Survey on Dairy Costs and Returns Report data, we reject the homogeneous technology hypothesis and find that the organic dairy technology is approximately 13 percent less productive. However, we find little difference in technical efficiency between organic and conventional farms when technical efficiency is measures against the appropriate technology. Key words: dairy, organic, productivity, propensity score matching, stochastic frontier, technical efficiency Carlos D. Mayen is assistant professor in the Department of Agricultural Economics and Agricultural Business, New Mexico State University. Joseph V. Balagtas is assistant professor and Corinne E. Alexander is associate professor, both in the Department of Agricultural Economics, Purdue University. This research was supported by the Economic Research Service, United States Department of Agriculture, through the cooperative agreement # 43-3AEL-5-80064, and by the Purdue University Agricultural Experiment Station. The authors thank Michael Schutz, Jeffrey Dorman, and two anonymous reviewers for helpful comments.