This volume presents recent progress in the improvement of the nuclear database needed for the development of Generation IV nuclear energy systems. The Generation IV International Forum (GIF) identified six advanced concepts for sustainable nuclear energy production at competitive prices and with advanced safety, with special attention to nuclear non-proliferation and physical protection issues, minimization of long-lived radiotoxic waste, and optimum natural resource utilization System groups have been established for studying these concepts in detail, and nuclear data are an inherent part of these studies. This book reviews the work recently performed for the development of these systems. The contributions include an up-to-date overview of recent achievements in sensitivity analysis, model calculations, estimates of uncertainties, and the present status of nuclear databases with regard to their applications to Generation IV systems. In the workshop, special attention was given to the identification of nuclear data needs from sensitivity analysis of benchmark experiments and the treatment of uncertainties. The proceedings contain overviews of several experimental program and recent results of interest for the development of Generation IV systems. Contents: Nuclear Data Needs for Generation IV Systems: Future of Nuclear Energy and the Role of Nuclear Data (P Finck); Nuclear Data Needs for Generation IV Nuclear Energy Systems OCo Summary of US Workshop (T A Taiwo & H S Khalil); Innovative Fuel Types for Minor Actinides Transmutation (D Haas et al.); Benchmarks, Sensitivity Calculations, Uncertainties: Sensitivity of Advanced Reactor and Fuel Cycle Performance Parameters to Nuclear Data Uncertainties (G Aliberti et al.); Computer Model of an Error Propagation Through Micro-Campaign of Fast Neutron Gas Cooled Nuclear Reactor (E Ivanov); Generating Covariance Data with Nuclear Models (A J Koning); Experiments: INL Capabilities for Nuclear Data Measurements Using the Argonne Intense Pulsed Neutron Source Facility (J D Cole et al.); Cross-Section Measurements in the Fast Neutron Energy Range (A Plompen); Recent Measurements of Neutron Capture Cross Sections for Minor Actinides by an JNC and Kyoto University Group (H Harada et al.); Evaluated Data Libraries: Nuclear Data Evaluation for Generation IV (G Nogu re et al.); Improved Evaluations of Neutron-Induced Reactions on Americium Isotopes (P Talou et al.); and several other important contributions. Readership: Graduate students and nuclear physicists interested in experimental nuclear physics, nuclear reactions modeling, and reactor physics, especially the development of Generation IV reactors."