After attending Pennsylvania State University, he served three years as a special agent with the US Army Counter Intelligence Corps until 1956, when he began his journalistic career as a reporter for the Reading (Pennsylvania) Times. Nine years later he become an investigative journalist for The Plain Dealer, and later took similar jobs with The Chicago Daily News and The Philadelphia Inquirer, where he was to join his collaborator James B. Steele. In 1997, Barlett and Steele became an editors-at-large for Time. In 2006, they moved to Vanity Fair as contributing editors. Over the years, Barlett and Steele wrote on such diverse topics as crime, housing, nuclear waste, tax loopholes, the decline of the middle class's standard of living, Howard Hughes, the role of big money in politics, oil prices, immigration and health care.