Concurrent constraint programming -- Specifications using multiple-conclusion logic programs -- Viewing a program transformation system at work -- Proving implications by algebraic approximation -- Sufficient completeness and parameterized proofs by induction -- Proving behavioural theorems with standard first-order logic -- How to realize LSE narrowing -- Compositional analysis for equational Horn programs -- Equation solving in projective planes and planar ternary rings -- From eventual to atomic and locally atomic CC programs: A concurrent semantics -- Concurrent logic programming as uniform linear proofs -- Three-valued completion for abductive logic programs -- A sequential reduction strategy -- On modularity of termination and confluence properties of conditional rewrite systems -- Syntactical analysis of total termination -- Logic programs as term rewriting systems -- Higher-order minimal function graphs -- Reasoning about layered, wildcard and product patterns -- Preserving universal termination through unfold/fold -- A logic for variable aliasing in logic programs.

This volume constitutes the proceedings of the Fourth International Conference on Algebraic and Logic Programming (ALP '94), held in Madrid, Spain in September 1994. Like the predecessor conferences in this series, ALP '94 succeeded in strengthening the cross-fertilization between algebraic techniques and logic programming. Besides abstracts of three invited talks, the volume contains 17 full revised papers selected from 41 submissions; the papers are organized into sections on theorem proving, narrowing, logic programming, term rewriting, and higher-order programming.