Although we often plead with our colleagues and students to be more “systematic,” we may not always be clear about what we mean. In biology, systematics is the “scientific study of the kinds and diversity of organisms and of any and all relationships among them” (Simpson 1961), the most important aspect of which is taxonomy, “the theory and practice of classifying organisms into groups on the basis of their relationships” (Mayr 1969). In political science, our organisms are political institutions. This article is a call for research in political systematics with suggestions for how the taxonomy of electoral systems might be developed.

Institutional taxonomy can play many roles in comparative politics. It can provide an appreciation of the existing and theoretical diversity of political institutions, provide the information necessary to construct a theory of institutional development, systematize the variables that affect and constrain political interactions, and provide the starting point for informed discussions of institutional reform. Current attempts to develop large standardized data sets in comparative politics (Rosenstone 1994), for instance, require institutional taxonomy if the effort is to be effective. Of course, this discussion would be moot if institutional taxonomy were already well established (with or without the term).