The informational and support requirements of ill-structured decision making activity are contingent upon the factors that have caused this lack of structure. This paper attempts to operationalize the notion of "semi-structure" by an examination of the effect of uncertainty and equivocality on the decision making process and suggests that the presence of the these dimensions creates different support requirements for the decision maker. These requirements are subsequently mapped onto the features of alternative types of technological support, with the intent of determining the efficacy of a particular technology for a particular type of decision making task. It is argued that a single technology may prove ineffective in supporting semi-structured decision making, and a rationale for technology integration is developed.