Brantley began his journalism career as a Summer Intern at the Winston-Salem Sentinel and, in 1975, became an Editorial Assistant at The Village Voice. At Women's Wear Daily he was a reporter and then editor, and later became the European Editor, publisher, and Paris Bureau Chief.
He became The New York Times drama critic in August 1993. He was elevated to chief theater critic 3 years later.
He calls them likes he sees them, but his reviews do not always reflect the success of a show. His 2003 review of Wicked, for instance, was not exactly a rave (though the show is still selling out regularly). On the performance of Idina Menzel as the Wicked Witch of the West, Brantley wrote,
Despite the green skin, Elphaba is a bizarrely colorless role, all furrowed-brow sincerity and expansive power ballads. Ms. Menzel miraculously finds the commanding presence in the plainness of her part, and she opens up her voice in flashy ways that should be required study for all future contestants on ''American Idol.''
After a poor review of the show, Of Mice and Men, James Franco tweeted his disapproval, and referred to Brantley as a "little bitch." Brantley responded to Franco's post in an interview with the New York Observer. "I like Franco’s work on film a lot," he said, "and he didn’t disgrace himself on stage. I hope he returns to Broadway some day. And of course he’s entitled to say whatever he likes about me, as long as it’s not libelous, and somehow I don’t think 'little bitch' qualifies."
Brantley, who is gay, is single and lives in New York City.