Adam Sisman was born in London in 1954, the eldest child of David and Marjorie Sisman. He has one sister, Lucy, a graphic designer.
He attended St Paul's School and then the University of Sussex, where he read history. After graduating, he worked in book publishing before becoming a writer.
In 1979 he married Robyn Swett (1949-2016), who later became known as a publisher and author in her own right.
Sisman's main work about James Boswell is Boswell's Presumptuous Task, for which he won the National Book Critics Circle Award in 2001.
Sisman is a prolific writer who is arguably best known for his 2015 biography of John le Carré, ingeniously titled "John le Carré: The Biography", available from AbeBooks.