In Chapter 1, I developed a model of some factors related to state supreme court performance. This model, in essence, contains the hypothesis that variations in state supreme court performance can be explained by two kinds of variables: institutional and contextual. I have suggested that the institutional characteristics of the state court system, such as the presence or absence of an intermediate appellate court, will have some effect on the kinds of decisions rendered by a state court of last resort. Furthermore, the determination of the effect of institutional characteristics on decision-making should be the focus of study by social scientists and court reformers simply because these structures can be modified in the interest of improving court performance. However, organizations do not exist in a vacuum--they are, in part, products of and dependent upon their environment. 1 Here is where non-institutional (or "contextual") variables come into play. Socioeconomic development and political culture will condition and limit the practice of politics in the state and will help to shape the structure of political organizations. In this chapter, I examine variations in the institutional characteristics of state court systems. The first section of the chapter is almost purely descriptive of differences among the fifty court systems. Here I also hope to demonstrate the need for a classification scheme for state court systems to simplify the study of these courts. I then study regional variations in institutional characteristics to illustrate the relationship between political culture and institutions as suggested in my model. Finally, I develop a sixfold classification scheme based upon institutional similarity for state supreme courts.