Complementarity and institutional change: How useful a concept?

The concept of institutional complementarity – i.e. the idea that the coexistence of two or more institutions enhances the functioning of each – is increasingly used to explain why institutions are resistant to change and why introducing new institutions into a system often leads to unintended consequences or failure to achieve the intended objective. While the concept is appealing and intuitive, in reality its utility for explaining change is less than straightforward. This paper utilizes examples from comparative political economy to, first, unpack and delineate the concept and address the issue of how to measure the strength or 'binding force' of complementarities. Second, it assesses the utility of the concept for explaining institutional change. It is suggested that one's view of the methods and utility of measuring complementarity will hinge importantly on one's general theory of institutions and institutional change. In the end, while institutional complementarities are significant, assessing their causal effect on institutional change is difficult and ambiguous in most instances. A better understanding requires that we embed complementarities within a more general theory of institutional change which takes a broader view of the ways in which institutions interconnect and change. iv ZUSAMMENFASSUNG Komplementarität und institutioneller Wandel: Wie brauchbar ist das Konzept?