Book excerpt: How much truth is there to the popular belief that science is a young person's game? Is America's older scientific community retarding economic growth? Using a unique data base and an interdisciplinary approach, the authors address these and other questions. They find evidence that exceptional contributions to science are more likely to be made by those under 40. Age matters, but not nearly as much for "average" scientists. Success in science also depends on RPRT--being in the "right place at the right time". Not all generations of scientists have equal access to the type of jobs that foster productivity, nor do they have the good fortune to be educated when path-breaking events are occurring in their field. Changing economic conditions in science have conspired to make those who entered science during the last 25 years less productive than their predecessors. In addition, extreme competition for jobs and grants can make scientists behave in a dysfunctional manner. The authors conclude that the absence of a national science policy can cause serious problems for the United States, and they outline a policy to boost productivity in American science. Clearly written, with many pointed examples, this work will appeal to anyone interested in science or science policy.