When considered together, conservation tillage and herbicide-tolerant (HT) cotton have the potential to increase certain environmental benefits (such as reduced soil erosion) while decreasing costs to producers. This study tests the hypotheses that the diffusion of conservation tillage positively influences the diffusion of HT cotton and vice versa. To test the hypotheses, state-level data HT cotton diffusion and conservation tillage diffusion were estimated using both ordinary least squares, two-stage least squares and simultaneous equation estimation techniques. To determine the quantitative effects of one technology's diffusion on the other, elasticities of the diffusion of HT cotton with respect to conservation tillage and vice versa were calculated. Based, on results from a three-stage least squares model, the null hypothesis that diffusion of each technology is independent of diffusion of the other can be rejected. Adoption of one technology appears to have a significant, positive effect on the adoption of the other technology.