These Proceedings report the scientific results of the Summer Study on Plural Rationality and Interactive Decision Processes orga nized jointly by the System and Decision Sciences Program of the Inter national Institute for Applied Systems Analysis (located in Laxenburg, Austria) and the Hungarian Committee for Applied Systems Analysis. The Study, which was held in Sopron over the period 16-26 Augus.t 1984, had a very special character. Sixty-eight researchers from sixteen coun tr es participated, most of them contributing papers or experiments. In addition many members of IIASA's Young...