Abstract The authors consider strategic information management from two contrasting perspectives — as an instrument of competitive advantage, and as a tool for reducing uncertainty. The first analysis draws on Porter's work on competitive advantage, where the impact of information on each strategic business unit, or value activity, is discussed in terms of maximized opportunity at each organizational level. For Porter, information means information technology, but data and carriers are considered separately in this paper. The strategic information manager's place in the organization is compared with the analogous functions of the systems manager or corporate planner and the authors suggest some criteria for successful implementation of the role model. The paper concludes with a discussion of the role of information in reducing uncertainty, and illustrations of megamarketing, or strategic manipulation of the environment.