The first Joint Meeting of the Austrian and Swiss Operations Research Societies was held at the University of Technology in Vienna, Austria, from 22-24 September 1980. A selection of the papers then presented are published in this volume. The papers included provide a picture of Operations Research as a discipline comprehending various methods and models. The volume is divided into two parts. The first part contains papers on mathematical programming and optimal control theory. Moreover, two papers on decision and game theory are included as well as two on biomathematical to ics. Being more heterogeneous, the second part, on stochastic models, includes such topics as queueing theory, econometrics and time series analysis. As a special feature of the symposium, a series of applications of OR models in energy planning were discussed, e.g., load and demand forecasting, power distribution and extension planning, reliability and work-safety, etc. These papers have been incorporated into parts one and two according to the models used. GUSTAV FEICHTINGER PETER !CALL Institut fUr Okonometrie und Institut fUr Operations Research und Operations Research mathematische Methoden der Wirtschafts- Technische UniversitHt wissenschaften Wien UniversitHt ZUrich November 198 I ix Gustav Feichtinger and Peter Kall (eds.), Operations Research in Progress, ix..