I consider the chapter on delegation in Formal Models of Domestic Politics to be unusually coherent. This is not patting myself on the back. Rather, the literature that this chapter summarizes, with its origins in the seminal work of Holmström, is of a piece. One paper follows another; all I had to do was follow the bread crumbs.

What, then, to add? As I have discussed previously, the second edition of my textbook features new models, new exercises, and clarifications. The new models push on both substantive and methodological frontiers, providing a mix of novel argument and novel technique. With this chapter, I was able to extend the theoretical narrative in an interesting direction while introducing a class of models that belonged somewhere in the text.

In particular: In the first edition, the chapter on delegation closed with a discussion of Gilligan and Krehbiel's extension of the Crawford-Sobel cheap-talk model to delegation and information transmission in legislatures. This seemed a natural segue to a recent literature on cheap talk with multiple senders, where Galeotti, Ghiglino, and Squintani's model of strategic information transmission networks has provided a framework for analysis of numerous political environments. Happily, a paper by Torun Dewan and Francesco Squintani provided the hook: their model of "Leadership with Trustworthy Associates" examines delegation to leaders. My chapter, which began with a model of delegation to bureaucratic agencies and grew to encompass delegation to legislative committees, thus now incorporates delegation by party elites to a leader tasked with making decisions on their behalf. The trail of bread crumbs is intact.

I do have one regret with this chapter. A pedagogical principle that guides the text is to present no more analysis than can be written on the blackboard and understood by Ph.D. students who have taken a semester of game theory and a semester of calculus. When that proves impossible with the original version of a model, I typically strip it down to something simpler; I try to avoid statements of the sort "X and Y show that Z is true." I wasn't quite able to do that with the Dewan-Squintani model without abandoning entirely the theoretical framework I wanted to demonstrate. There are a couple of hand waves. I hope the accompanying discussion compensates, but readers will be the judge.