Is the basis on which science policy has been conducted since World War II still valid for the twenty-first century? Does a close partnership between the scientific community and the government offer unique advantages in the progress of research and development? Since its publication in 1945, the report by Vannevar Bush - Science: The Endless Frontier - has been the touchstone of all discussions about science policy. That report, formulated out of the experience of World War II, set forth a case for an enduring partnership between scientific institutions and the federal government both as a means for generating new technology and as the foundation for achieving technological superiority over America's potential foes. In this timely reexamination of such issues, a group of the most distinguished economists who have written on science policy over the past decade evaluates the continuing relevance of Bush's arguments and conclusions.