Although insightful and convenient, whether Porter's model is also a useful approach to predict superior performance is another issue and an important research topic. The knowledge of the usefulness of Porter's model would be enhanced if a number of studies that relate to this model are critically reviewed. In conducting such a review, it would be best not only to point out the findings of the studies reviewed, but also-more importantly-to assess their conceptualization of Porter's model as well as the methodologies deployed. After this literature review, it would also be of interest to compare new empirical evidence with that found in the studies reviewed.