An improviser for whom I have a great deal of respect once told me that this was the only book you'll ever need for improv. She was right. It explains it in a coherent, entertaining way and convinces you that you or anyone could do it. What is needed to improvise? What works best or worst? It may not be the only book you want to read, but it explains the basics and is the only one you'll NEED.

Still need more? Then read this. It gets elemental in its explanation of the basics, devoting a large amount of its pages to the idea of status. It will change the way you look at scenes and at life, and introduces some very intriguing and useful ideas. The last part of the book is about mask work, and it's one of the most interesting things I've ever read, but only tangentially applies to improv.

No, I have not read this. But here's why I think it would be valuable: it comes with a dvd of some great improv teams, which, unless you're a student or performer in Chicago or another improv-laden city, you won't get the chance to see. And, second to performing it or taking a workshop, seeing it in action is the most valuable thing you can do.