This book has the potential to become essential reading for anyone in applied economics. Scott has gone out of his way to write a tour de force on the econometrician's toolkit. He covers basic principles of regression, DAGs, RD, synthetic controls, and a host of other identification strategies and estimators.
The reading is pleasurable, too. Unlike a lot of economics papers or books, you can sit down and enjoy the writing. In some sense, it's very similar to Angrist and Pischke's Mostly Harmless Econometrics. But Scott's florid style (that I'm sure stems from his days as a poet) is striking. Words are artfully chosen but not to the extent that there are Hemingway-esque non sequiturs.
Don't sleep on this book and think it's identical to MHE. If you're a PhD student, recent PhD grad, or thinking about applying to a PhD program, read this! Scott covers topics not included in MHE, and also provides code for you to execute. The examples to motivate the concepts and highlight the code are masterfully captured.
And while the book isn't perfect, remember it's only a rough draft. You'll find typos and notational conflicts. (Hell, I'm sure this review has typos in it!) But they're not so jarring that you miss his logic. To my knowledge, Yale Press will seriously scrutinize the editorial process. So, when the book is completed, it'll be even better. Scott has even written on Twitter stating he's going to include some additional material on the new difference-in-differences techniques. So, be on the lookout for the updated version. I know I'll buy a copy to reference.
Kudos, Scott, and thanks for being a really splendid guy!