The calculus of relations turned into an important conceptual and methodological tool in computer science. The methods presented in this book include questions of relational databases, applications to program specification, resource-conscious linear logic, semantic and refinement consideration, nonclassical logics for reasoning about programs, tabular methods in software construction, algorithm development, linguistic problems, followed by a comprehensive bibliography. The reader gets an overview of the wide-ranging applicability of relational methods in computer science.