The debate over GM crops is one of the most controversial issues of recent decades. The debate has many dimensions, including environmental impacts, benefits and risks to human health, intellectual property rights, adequacy of biosafety regulations, and fundamental ethical acceptability. The potential benefits of GM crops are numerous, including improved nutritional value, decreased production costs, resistance to pests, and reduced pesticide use. However, there are also substantial and complex health, environmental, and social risks, including effects on gene flow and biodiversity, creation of new toxins or allergens in food, consolidation of seed companies, and restricted access to genetic information and methods. Current US regulations are imposed only on crops produced through recombinant DNA methods, though all of these risks apply to crops modified through conventional biotechnologies as well. I argue that this current regulatory system impedes progress by presenting large obstacles to even low risk GM crops with medical and economic benefits. I suggest that a better approach would be a tiered system that takes into account the specific biological properties of the modified traits, the biology of the crops in which they are produced, and the environments in which they are grown.