Much has been said about opportunities for the strategic use of information technology by organizations aiming to gain a competitive advantage. However, not much is known about the actual process by which opportunities for the use of strategic information systems are identified. While various planning methodologies have been proposed, there is at present a paucity of information on empirical results obtained from applying them, and on their effectiveness, efficiency, and specificity. This article presents the results of a field experiment aimed at applying and comparing two well-known methodologies for identifying information systems opportunities from a competitive advantage perspective-Porter's value chain and Wiseman's strategic thrusts methodology. An instrument was prepared to operationalize each methodology, which was then applied in two matched sets of 10 medium-sized enterprises. Both methodologies were found to be effective in generating a significant number of ideas for information systems worthy of implementation. Similarities and differences are analyzed and discussed in terms of the number, estimated implementation costs and duration, managerial level, and decision to implement the applications identified by the two methodologies. These applications are also classified from the perspective of both Porter's and Wiseman's framework. The results seem to indicate that while there is an overall similarity between the two methodologies, there are certain differences that show the more outward orientation of the strategic thrusts framework and its greater attractiveness for organizations in unstable environments.