Some of the most fruitful insights generated by social science in recent decades flow from explorations of how institutions, understood as sets of regularized practices with a rule-like quality, structure the behavior of political and economic actors. It is not surprising that attention has now turned to the second-order problem of explaining when and how institutions change. In conceptual terms, however, this task is intrinsically difficult. By their nature, analyses designed to explain why institutions have a persistent impact on behavior tend to overstate the solidity of institutions. Acknowledging their plasticity raises questions about when institutions should be seen as determinants of behavior and when as objects of strategic action themselves.

This problem afflicts rational-choice approaches to institutions with particular intensity because of the elegant solutions such analyses have devised to explain the force and persistence of institutions. Typically, they see institutions as patterns of regularized behavior that reflect Pareto-optimal equilibria or subgame perfect solutions to collective actions dilemmas, stable because the actors cannot improve their positions by defecting from the pattern of behavior (Shepsle 1989; Koremenos et al. 2003; Greif and Laitin 2004). Therefore, institutional change happens only when ceteris is no longer paribus, that is, when shocks exogenous to the system of institutions alter the context. Institutional change becomes a response to shocks. Such analyses posit a radical separation between periods of institutional stability and periods of change (often labeled “critical junctures”) that rarely explain well how institutions emerge from disequilibrium at such junctures (see Thelen 2004; the introduction to this volume).