This empirical study of conservation tillage adoption relies on the logit model applied to fieldlevel information on agents’ attributes and county-aggregated measures of agents’ choices. The methodology treats the aggregated data as an expected value—the area-weighted group average of individual probabilities of choosing conservation tillage—subject to a measurement error. Using 2002 and 2004 data for Iowa, we estimate field-level costs of the adoption of conservation tillage. The results indicate that adoption is significantly affected by soil characteristics and crop rotation and highlight the heterogeneity in adoption costs when controlling for these characteristics.