The aim of this paper is to present tools or techniques for an interactive multiattribute decisionmaking with the decision maker's incomplete information. That is: (1) We formally describe mathematical models under certainty and uncertainty for establishing pairwise dominance, where the incomplete information becomes the set of constraints in the model. (2) We present a description on styles of incomplete parameter value information. (3) The characteristic of a weak dominance is described. When the decision maker is not willing or able to provide more information on parameters, the weak dominance technique is useful for a final choicemaking. (4) We propose a dominance graph and also present an algorithm of generating the dominance graph based on the information of pairwise dominance. The dominance graph compactly displays the dominance structure of all alternatives, thus it can be used for aiding the selection of preferable alternatives. (C) 1997 Published by Elsevier Science B.V.