This volume contains most of the papers presented at the 6th Logic Programming Conference held in Tokyo, June 22-24, 1987. Topics of particular interest are constraint logic programming and parallelism. The effort to apply logic programming to large-scale realistic problems is another important subject of these proceedings.

From unification to constraints.- CS-Prolog: A generalized unification based constraint solver.- Update propagation network — A framework for constraint programming.- Mendels: Concurrent program synthesis system using temporal logic.- Analogical program synthesis from program components.- Deriving a compilation method for parallel logic languages.- The art of building a parallel logic programming system or from zero to full GHC in ten pages.- of a package system into Prolog.- KPR: A logic programming language-oriented parallel machine.- A preliminary evaluation of a parallel inference machine for stream parallel languages.- Managing search in parallel logic programming.- Inductive inference of regular languages based on model inference.- Polymorphic type inference in Prolog by abstract interpretation.- Proving partial correctness of guarded horn clauses programs.- Knowledge representation and inference based on first-order modal logic.- Manipulation of embedded context using the multiple world mechanism.- Generating natural language responses appropriate to conversational situations - in the case of Japanese -.- An approach to speeding up the Prolog-based inference engine KORE/IE.- Test generation for large-scale combinational circuits by using Prolog.- Concurrent execution of Prolog transaction.