The purpose of this issue of "New Directions for Evaluation" is to examine, comparatively, the practical application of theorists' approaches to evaluation by examining four evaluations of the same case. The thought is that when asked to evaluate the same program (holding the case constant), the practical distinctions between theorists' approaches become evident. The authors also speculate that subtler differences in approaches will be highlighted, and surprising similarities will emerge. The authors of this chapter describe and compare the four theoretical perspectives represented by the theorists writing Chapters Three through Six, providing additional comparative analysis based on their published works, with the intent of providing a general understanding of their approaches. Each of the invited authors was asked to explain what they would actually do when confronted with designing an evaluation for a case school, Bunche-Da Vinci, which was presented in Chapter One.