The commercialization of transgenic crops has engendered significant resistance from environmental groups and defensive responses from industry. A part of this struggle entails the politicization of science as groups gather evidence from the scholarly literature to defend a supportive or opposing position to transgenic crop commercialization. The authors argue that novel technology development and associated scientific uncertainty have led to two competing approaches to risk management: precaution and ex post trial and error. In this paper we use the controversies over currently commercialized transgenic crops to analyze the debate over these competing approaches. We also suggest a hybrid approach that incorporates a precautionary selection process, but also relies on ex post trial and error after commercialization. This approach is labeled precaution through experience since the development of a technology's characteristics would ideally take into account previous experience with similar technologies, or rather technologies with similar applications. The authors argue that substantial public participation and dialogue is needed to identify socially desirable crop traits to guide research and development. Policy tools are also recommended that provide incentives to private-sector firms to engineer the identified traits into crops.