From August 28 to August 30, 1980 the IV. Bonn Workshop on Combinatorial Optimization was held at the Rheinische Friedrich-Wilhelms-Universitat, Bonn. It was organized by the Institut fur Okonometrie und Operations Research and generously sponsored by the Deutsche Forschungsgemeinschaft through the Sonderforschungsbereich 21.
Altogether 54 scientists from 16 different countries gathered at this meeting in a highly stimulating atmosphere. This volume constitutes a part of the outgrowth of the workshop and is based on the lectures presented there. The papers cover a broad spectrum of the field from submodular functions to perfect graphs, and from vertex packing to scheduling and subtree extension. All papers were subjected to a careful refereeing process