This volume contains the proceedings of the Fourth Workshop on Languages and Compilers for Parallel Computing, held in Santa Clara, California, in August 1991. The purpose of the workshop, held every year since 1988, is to bring together the leading researchers on parallel programming language design and compilation techniques for parallel computers. The papers in this book cover several major topics, including languages and structures to represent programs internally in the compiler, techniques for analyzing and manipulating sequential loops in order to generate a parallel version,...