From 1962 onwards, Janson would gradually focus more on notated music and gained recognition with works such as November (1962) for piano and Vuggesang for 48 strykere og sopran (1963).
The same year also saw Janson’s international breakthrough at the ISCM World Music Days with the work Kanon for chamber orchestra and audio tape.
[4] Political themes have often served as an inspirational source for Janson, and he is one of the few Norwegian composers who has had a demonstration held against a performance of one of his works, Interlude for orchestra og accordeon, a work written as a salute to Arne Treholt, who was sentenced to life imprisonment for espionage for the Soviet Union in a trial in 1985.
In the more humorous-political genre, Valse Triste marks a milestone – and is viewed as a critical collage of early 1970s Norwegian cultural debate.
More recent works with a clear political trait include 2003’s A Bagdad Blues (not for Blair, not for Bush) which Janson wrote in protest against the Operation Iraqi Freedom invasion of Iraq.