MCDA: Theory, practice and the future

We offer thoughts on issues and directions in multi-criteria decision analysis (MCDA) that seem likely to be prominent in the next few decades. We look first at recent history and will emphasize the interplay between theory and practice. Theory concerns the design and logical analysis of methods, models, and algorithms for formulation, assessment, and decision in generic types of situations addressed by MCDA. Practice involves applications of methods, models, and algorithms to concrete decision problems. We take the conventional position that theory and practice complement each other and should be mutually enriching. Without theory, practice assumes an ad hoc character that runs the risk of ossifying into shamanism. And without the lessons of practice, theory is liable to levitate into esoteric and irrelevant abstractions.