Many of the stories in Shell Collector, take place in Africa and New Zealand, where he has worked and lived. In a 2004 online interview for the Washington Post, Doerr mentioned that his next work may involve occupied France during World War II and their subversive use of radios against the Nazis. The struggles in writing this book are documented in his newest book, a non-fiction memoir entitled Four Seasons in Rome: On Twins, Insomnia, and the Biggest Funeral in the History of the World. This book was published by Scribner in the US in 2007 and by Fourth Estate in the UK in 2008. He also writes a column on science books for the Boston Globe and is a contributor to The Morning News.
Doerr is married with twin sons and lives in Boise, Idaho. From 2007–2010 he was considered the 'writer-in-residence' for the state of Idaho.