A Director Prepares by Anne Bogart - great theoretical book on directing and storytelling
The Empty Space by Peter Brook - great theoretical book on theatre itself. Deeply inspiring.
The Collaborative Habit by Twyla Tharp - the 2nd in a series, after The Creative Habit, which is also a great book on building a technique to find inspiration and prepare work. The Collaborative Habitis filled with specific, hard-won advice on collaborating wtih a variety of roles and institutions.
Conversations with Anne by Anne Bogart - interviewing dozens of successful director with differing aesthetics