Swedish writer and journalist, born 17 January 1944 in SšdertŠlje, Sweden.

In 1964 he started working as a journalist at the left-wing magazine Folket i Bild. In 1973 he and colleague Peter Bratt exposed the illegal activities of Swedish military intelligence in what became known as the IB-affaire. This excellent piece of investigative journalism was rewarded with a 10 month prison sentence for espionage (a ridiculous charge, but the prosecution had to use it to circumvent the freedom of press act).

Since then Jan Guillou has moved on to become one of Sweden's most successful writers. He is best known for a bestselling (in Sweden, at least) 10 novel series of Tom Clancy-style thrillers about secret agent Carl Hamilton. Ondskan, a partly autobiographic novel about bullying at an upper-class boarding school, has also become a classic. When it was filmed in 2003 it was nominated for an Oscar.