To write The Snowball, I spent more than five years interviewing Warren Buffett, both in person and on the phone. For weeks on end I sat in his office or traveled with him observing him work. Some of my most valuable insights came from my own experiences with him. I also interviewed his family, friends, former classmates, business associates, and others—250 people in all. Some of these interviews continued for days and I interviewed many people several times.
Warren gave me virtually unlimited time, and let me roam with surprising freedom among the files and correspondence in his exhaustive collection; it was especially fortunate that he and many of his friends and family members were letter-writers. Berkshire Hathaway’s files contained material that helped establish a timeline and flesh out details. I also relied on my own growing understanding of Warren, and at times on my direct knowledge of events. Certain disagreements among sources are aired in the endnotes.
Quotes appear throughout the book to illuminate the narrative. Most quotes are from recorded interviews, and have been edited only for clarity and length. Sources were cited unless the interviewee asked not to be named.
During their interviews, many people recalled remarks from past conversations. Sometimes the events they were describing had taken place decades earlier. It would be naive to assume that all of these quotes are verbatim recollections of every word spoken. Nevertheless, I found them very helpful in conveying the substance of an incident or conversation. Their sources can be found in the endnotes.
In the end, my own extensive experience with Warren and the thousands of jigsaw puzzle pieces given me by so many sources came together in this portrait of a fascinating and deeply complex man.