Evaluation of scientific research, particularly of research which is supported by government funds, is a matter of growing concern in virtually every nation. It is no longer adequate to expect that the value of investments in research will be judged in long-term historical perspective. Resources are scarce and policy-makers are looking for ways to assure that these resources are used in the most effective way. From the life-or-death evaluations of academic research institutes in the post-communist countries to the Government Performance and Results Act(GPRA) in the United States, research evaluation has become a topic of utmost importance in science policy. Evaluation often has substantial consequences for researchers and research institutions, including restructuring, shifting of priorities, budget reductions, or evenclosures. Therefore it is essential that evaluation is done systematically and objectively, with methodologies that can be understood and trusted by those concerned. This book is based on a NATO Advanced Research Workshop, co-organized by the Academy of Sciences of the Czech Republic and the American Association for the Advancement of Science. It describes a range of the most up-to-date methods of science evaluation and the experience with their implementation in many countries. This book can be of interest to researchers, policy-makers, practitioners of science evaluation and many others interested in science policy.