This volume contains the proceedings of the Ninth Conference on Fundamentalsof Computation Theory (FCT 93) held in Szeged, Hungary, in August 1993. The conference was devoted to a broad range of topics including: - Semanticsand logical concepts in the theory of computing and formal specification - Automata and formal languages - Computational geometry, algorithmic aspects of algebra and algebraic geometry, cryptography - Complexity (sequential, parallel, distributed computing, structure, lower bounds, complexity of analytical problems, general concepts) - Algorithms (efficient, probabilistic, parallel, sequential, distributed) - Counting and combinatorics in connection with mathematical computer science The volume contains the texts of 8 invitedlectures and 32 short communications selected by the international program committee from a large number of submitted papers.