An interactive negotiation procedure for large scale systems with multiple objectives is proposed. It is assumed that there are multiple decision-makers, who have their own multiple objectives and who are dependent on each other via common resources or physical connections. The negotiation procedure includes two repeated main steps: the decision-makers' independent multicriteria optimization of their subsystems, and a convenient step for tradeoff between the decision makers. Assumptions guaranteeing the convergence of the negotiation scheme are established; among these one assumption, concerning independence of subsystems, is essential. The negotiation procedure is applied in the operation planning of two coupled hydroelectrical power systems of the southeast region of Brazil, and simulation results are included to show its usefulness in solving real world problems. The same operation planning problem is also solved by the SEMOPS method. A comparison is made from the viewpoint of methodology, practice and computational effort. The results obtained from the comparisons show that the proposed scheme is very effective in solving complex, multiobjective problems. Finally, conclusions and further work are addressed. © 1991.274691697Cardarelli, Iteractive decisions in large scale systems with multiple objective: An application in power systems (1987) MSc Thesis, , Universidade Estadual de Campinas (UNICAMP) Campinas, Brasil, (in Portuguese)Changkong, Haimes, (1983) Multiobjective Decision Making: Theory and Methodology, , North-Holland, New YorkChankong, Haimes, Thadathil, Zionts, Multiple criteria optimization: A state-of-the-art review (1985) Decision Making with Multiple Objectives, , Y.Y. Haimes, V. Chankong, Springer, New YorkGomide, Hierarchical multistage, multiobjective impact analysis (1982) PhD Dissertation, , Dept. of Systems Engineering, Case Western Reserve University, Cleveland, OH, USAGomide, A multiobjective, hierarchical optimization method for multistage systems (1981) Progress report no. 2, , Systems Engineering Department, Case Western Reserve University, Cleveland, OH, USAGomide, Tarvainen, Haimes, Iterative negotiations on multiple objectives in large scale systems (1984) 9th World Congress of IFAC, , Budapest, HungaryHaimes, Chankong, Optimization based methods for multiobjective decision-making: Overview (1983) Large Scale Systems, 5, pp. 1-33Haimes, Li, Hierarchical multiobjective analysis for large-scale systems: Review and current status (1988) Automatica, 24Hwang, Masud, (1979) Multiple Objective Decision Making Methods and Applications, , Springer, BerlinKeeney, Raiffa, (1976) Decisions with Multiple Objectives: Preferences and Value Tradeoffs, , Wiley, New YorkMonarchi, Kisiel, Duckstein, Interactive multiobjective programming in water resources A case study (1973) Water Resources Research, 9, pp. 837-850Sage, (1977) Methodology for Large-Scale Systems, , McGraw-Hill, New YorkStackelberg, (1952) The Theory of the Market Economy, , Oxford University Press, Oxford, UKTarvainen, Hierarchical multiobjective optimization (1980) Ph.D Dissertation, , Dept. of Systems Engineering, Case Western Reserve University, Cleveland, OH, USAYu, (1985) Multiple-Criteria Decision Making, , Plenum Press, New YorkZimmermann, Zadeh, Gaines, (1984) Fuzzy Sets and Decision Analysis, , North-Holland, AmsterdamZionts, Wallenius, An interactive programming method for solving the multiple criteria problem (1976) Management Sci., 22, pp. 652-663Zionts, Wallenius, An interactive multiple objective linear programming method for a class of underlying nonlinear utility functon (1980) Working Paper 451, , School of Management, SUNY, Buffalo, N.Y