This book presents the proceedings of the 12th Annual Symposium on Theoretical Aspects of Computer Science (STACS 95), held in Munich, Germany in March 1995. Besides three invited talks, the book contains revised versions of 53 research papers selected from a total of 180 submissions. The contributions address all current aspects of theoretical computer science; they are organized in sections on complexity theory, automata theory, algorithms, logic, theory of parallel computing, communication theory, graph theory and databases, and computational geometry.