The scientific community has an important role to play in public policymaking. However, several difficulties impede productive incorporation of science into decisionmaking. One difficulty is that most scientists lack essential knowledge and experience of decision and policymaking processes at all governmental levels, and therefore do not know how to participate effectively in these processes. If a scientist wants to be more effective, he or she has to take political discourse seriously. A second aspect is that a holistic scientific viewpoint is necessary to improve decisionmaking. Methods to understand behavior at the whole-system level - both natural and human dimensions - are required to replace the reductionistic approaches that attempt to solve problems piecemeal. The global extent of environmental problems is a clear signal that piecemeal problem solving does not result in effective decisionmaking. The challenge rests in developing a transparent process in which scientists and policymakers share information equally about scientific needs, political realities, and economic choices.