This volume contains a selection of papers presented at the Conference of the European Association for Computer Science Logic, held at Swansea in September 1993. Topics discussed include set constraints, lambda calculi, process algebras, program semantics, fixed-point logics, Horn clauses and more.

The complexity of set constraints.- On duality for the modal ?-calculus.- Short proofs of tautologies using the schema of equivalence.- Process algebra with combinators.- Is game semantics necessary?.- The model theory of concurrency.- From semantics to rules: A machine assisted analysis.- On the reasons for average superlinear speedup in parallel backtrack search.- Negation as inconsistency in PROLOG via intuitionistic logic.- Approximable minimization problems and optimal solutions on random inputs.- Bounded-arity hierarchies in fixed-point logics.- Petri nets and the equivalence problem.- Logical aspects of set constraints.- Oracles and quantifiers.- A Horn clause that implies an undecidable set of Horn clauses.- Higher-order action calculi.- A generic strong normalization argument: Application to the Calculus of Constructions.- Data types, infinity and equality in system AF 2.- Normalization for typed lambda calculi with explicit substitution.- Program transformation and proof transformation.- Incorporating generalized quantifiers and the least fixed point operator.- “The semantics of the C programming language”.