Book excerpt: The research described in this book addresses the semantic gap between logic programming languages and the architecture of parallel computers - the problem of how to implement logic programming languages on parallel computers in a way that can most effectively exploit the inherent parallelism of the language and efficiently utilize the parallel architecture of the computer. Following a useful review of other research results, the first project explores the possibilities of implementing logic programs on MIMD, nonshared memory massively parallel computers containing 100 to 1,000 processing elements. The second investigates the possibility of implementing Prolog on a typical SIMD machine, called a Distributed Processor Array. The author's objectives are to define a parallel computational paradigm (the Extended Cellular-Dataflow Model) that can be used to create a Parallel Prolog Abstract Machine as a general starting point for implementing logic programming languages on parallel computers, to exploit the different types of parallelism of these programs, to define an efficient parallel logic machine, to explore the possibilities of implementing logic programming languages on array processors, such as the DAP, to invent parallel implementation techniques for effectively executing Prolog on the DAP, and to define a parallel extension of Prolog that is able to utilize the processor aggregate of the DAP for effectively solving numerical subproblems within logic programs Peter Kacsuk is with Multilogic Computing Ltd. of Budapest, Hungary.