Quantitative Decision Support Modeling received most of its development during the 60's. The result was a normative procedure, following the Operations Research tradition. Following the same tradition, the results carefully analysed by sensitivity procedures allowed their practical implementations. The natural and required evolution towards Multicriteria Decisions has been much more controversial. The "theoretically correct" procedure presented difficulties for its practical implementation. North-American and European challengers appeared, where the normative structure was replaced by a Decision Support one. The paper presents and comments this panorama with its contrasts.
decision support; model; analysis; process