Safety and risk analyses are complex by nature and require significant effort, extensive skills and experience, analytical tools and supporting information. To reduce the effort and to enhance the analytical capabilities for present and future generation of nuclear systems, an Integrated Training and Accident Analysis System (ITAAS) has been developed. The primary objective of the ITAAS combined software/hardware system is to provide a comprehensive and integrated accident and safety analysis capability for research and technical support organizations and other potential users (such as regulators) having responsibilities related to nuclear power plants (NPPs), research reactors, and other nuclear facilities. More specifically, and in the context of well executed accident and safety analyses, ITAAS provides: Proven Analytical Tools via the Deterministic Analysis Module based on RELAP5 and the Probabilistic Analysis Module based on SAHPIRE, Specialized Skill Development via a Training Module, and a Broad Knowledge Base via a Reference Module. The modular design and connectivity of ITAAS allows for enhancement of existing, and addition of new modules, primarily in the context of future implementation of new analysis tools and their associated training requirements. ITAAS can be configured for specific NPPs or other nuclear installations as may be dictated by facility, organization ormore » country needs. The first ITAAS system has been installed at the Kursk 1 NPP in Russia. (authors)« less