These two quotes, the first by a pair of international law scholars, the second by a political scientist, are classic and important statements, representing two well-respected schools of thought. These quotes are also not quite consistent with one another. Additionally, we have the following descriptive statistics:

1. • Almost half of economics agreements contain a formal punishment provision.

2. • About one-sixth of security agreements contain such a provision.

How then do we reconcile these two statements not only with each other but also with the empirical reality? Specifically, first, why do so many economics agreements contain punishment provisions, a fairly strong form of enforcement provision, if “well-designed” agreements are unlikely to need them? Second, if security cooperation is so risky, why do so few security agreements contain formal punishment provisions?

In this chapter, I provide a theory of punishment provisions that includes an articulation of when such provisions are themselves part of a well-designed, “practical” agreement. I also use this design feature as a point of departure for an analysis of potentially informal provisions within formal international law, thereby addressing the unexpected absence of formal punishment provisions in particular cooperative endeavors. Of course, a key challenge in the study of informalism is identifying and quantifying what is indeed informal across more than a few, well-known cases. In this chapter, I offer a theory and method to analyze the role of informalism across the COIL random sample.

I first present a theory of punishment provisions and test the theory against the COIL data. I then turn to a consideration of informal punishment provisions. I briefly review a few important scholarly contributions on informalism as well as some important literature on compliance and the need for punishment provisions.