"This project started many years ago, as an article-length project on the apparent diffusion of new models of courts throughout Latin America. A paper Dan Brinks was writing for APSA dovetailed with a paper Abby Blass was writing for a graduate seminar, and the project evolved through conversations between the two authors after that. Both Abby and Dan had other projects to attend to, so the collaboration moved slowly, but we both felt it was intellectually productive. In its early stages in particular, each of the authors contributed important elements and carried out a mutual back and forth that makes it difficult to separate each author's contributions to the initial conceptualization and measurement exercises. Similarly, the basic argument evolved outof conversations between the authors, with each pushing the other to clarify and specify the argument further. Through conceiving and writing the pieces we have called "Conceptualization" (now an article in the International Journal of Constitutional Law, and largely contained in chapter 2 and the Appendix) and "Determinants" (the theory and quantitative analysis that underpins chapters 3 and 4), we collaborated fully. This is the core of the intellectual contribution of the book, and our joint work on these pieces is the principal, though not the only, reason Abby is credited as a co-author"- This book traces the development of constitutional courts in Latin America, and develops concepts such as judicial autonomy and authority. It aims to understand the design of judicial institutions and combines qualitative and quantitative evidence to explore the basic purpose of constitutional justice.