In the last few years we have all become daily users of Internet banking, social networks and cloud services. Preventing malfunctions in these services and protecting the integrity of private data from cyber attack are both current preoccupations of society at large. While modern technologies have dramatically improved the quality of software, the computer science community continues to address the problems of security by developing a theory of formal verification a body of methodologies, algorithms and software tools for finding and eliminating bugs and security hazards.This book presents lectures delivered at the NATO ukryj opis