Andrew Carroll is the editor of several New York Times bestselling collections of letters, including Letters of a Nation and War Letters: Extraordinary Correspondence from American Wars, as well as the critically-acclaimed Behind the Lines: Powerful and Revealing American and Foreign War Letters, And One Man's Search to Find Them. War Letters was the inspiration for the PBS documentary of the same name, which was produced by American Experience. The audio version of the book was nominated for a Grammy.

Carroll is also the founder and director of the Legacy Project, a national, all-volunteer initiative that seeks out historically significant letters written in times of war. To date, the Legacy Project has received an estimated 75,000 never-before-seen wartime correspondence representing every military conflict in American history.

In January 2004, the Presidential Inaugural Committee used War Letters and Behind the Lines as the inspiration for its "Saluting Those Who Serve" event. Famous actors, musicians, and American heroes all read from letters in the books, and the event was attended by 15,000 troops and the President of the United States.

Carroll's interest in letters began in 1989 after his home in Washington, D.C. burned down. Although no one was hurt in the fire, all of Carroll's possessions, including his letters, were destroyed. The loss prompted Carroll to realize the value of letters and how important it is to preserve them for posterity.

Carroll is fast becoming one of the nation's foremost military historians, and his efforts to promote the value of letters and the art of letter-writing have been profiled on Oprah, NBC's Nightly News with Tom Brokaw, FOX News, CNN, The History Channel (two different documentaries), C-Span, National Public Radio, CBS Sunday Morning, the Today Show, Good Morning America, and Nightline (which devoted a full broadcast to the Legacy Project). Carroll was featured as a Person of the Week on ABC's World News Tonight.

Carroll and/or his Legacy Project have also been profiled in the New York Times, USA Today, the Wall Street Journal, New York Times Sunday Magazine, US News & World Report, Newsweek, Time magazine, and almost every major newspaper in the United States. Carroll has also been a contributing editor and/or writer to many local and national publications, including Time magazine, the New Yorker, Guideposts, and National Geographic.

In 2001, Carroll revived the "Armed Services Editions" (ASEs), which are pocket-sized books made especially for the military and handed out to U.S. troops abroad. More than 1,300 titles in all were first published during World War II, including mysteries, biographies, crime stories, adventure novels, and classic works of literature. (The original ASEs were discontinued in 1947.) Carroll has been working with major publishers to reissue them, and he has distributed hundreds of thousands of free ASEs to U.S. servicemen and women around the world, including thousands of books he personally handed out in Iraq.

Carroll graduated magna cum laude from Columbia University in 1993, and, among other accolades, he is the recipient of the DAR's Medal of Honor; The Order of Saint Maurice, bestowed by the National Infantryman's Association; and The Free Spirit Award, presented by the Freedom Forum.