These Proceedings report the scientific results of an International Workshop on Methodology and Software for Interactive Decision Support organized jointly by the System and Decision Sciences Program of the International Institute for Applied Sys tems Analysis (nASA, located in Laxenburg, Austria) and The National Committee for Applied Systems Analysis and Management in Bulgaria. Several other Bulgarian institutions sponsored the Workshop - The Committee for Science to the Council of Ministers, The State Committee for Research and Technology and The Bulgarian In dustrial Association. The...