This volume contains selected papers presented either at the Oberwolfach Conference on Operations Research, February 1987, or at the three-day workshop on Advanced Computation Techniques, Parallel Processing and Optimization organized by IIASA and the University of Karlsruhe, which immediately followed. The aim of the conferences was to discuss recently developed methods in optimization theory and their practical implementation using advanced computation techniques, especially in parallel processing. The volume is divided into five sections: I. Algorithms and Optimization Methods II. Optimization and Parallel Processing III. Graph Theory and Scheduling IV. Differential Equations and Operator Theory V. Applications.