Robert Caro on the biographer's craft

He's written one volume about Robert Moses and four (with one to come) about Lyndon Johnson. In this Nieman Foundation Q&A session, Robert Caro talks about how he works: "I never interview by telephone. You learn so much from people's faces … One rule I have is, no matter how late it is, I will type up that interview before I go to sleep because I want to have it in my mind as fresh as possible, what my impressions were, how he acted when he was saying things."