Although the adoption of GM crops has been very rapid in countries that have approved them, there has been resistance in many other countries, particularly in Japan and the European Community. The complexity of the social issues driving this resistance is illustrated by the fact that the countries most resistant to adoption of the technology are also by far the largest users per hectare of pesticides known to cause health and environmental problems. A systems-level approach to evaluation of the relative value and risk of GM technology would entail studies of how this technology might reduce pesticide use in intensively managed crops, conserve soil by adoption of reduced tillage methods, or reduce human health risks.