Outranking methods as tools in strategic natural resources planning

Two outranking methods, ELECTRE III and PROMETHEE II, commonly used as deci sion-aid in various environmental problems, and their applications to decis ion support for natural resources management are presented. These methods r epresent 'the European school' of multi-criteria decision making (MCDM), as opposed to 'the American school', represented by, for instance, the AHP me thod. On the basis of a case study, outranking methods are compared to so f ar more usually applied techniques based on the ideas of multi attribute ut ility theory (MAUT). The outranking methods have been recommended for situa tions, where there is a finite number of discrete alternatives to be chosen among. The number of decision criteria and decision makers may be large. A n important advantage of outranking methods, when compared to decision supp ort techniques most often applied in today's natural resources management, is the ability to deal with ordinal and more or less descriptive informatio n on the alternative plans to be evaluated. Furthermore, the uncertainty co ncerning the values of the criterion Variables can be tal;en into account u sing fuzzy relations, determined by indifference and preference thresholds. The difficult interpretation of the results, on the other hand, is the mai n drawback of the outranking methods.