Trenaman won So You Think You're Funny? in 1994 and went on to write additional material for shows such as Head on Comedy, Lenny Henry in Pieces and Haywire, and comedians such as Harry Enfield, Johnny Vaughan and Phil Kay. The Lenny Henry special which he contributed to was winner of the Golden Rose of Montreaux in 2001.
Trenaman has been credited with writing material for Is It Bill Bailey? and Never Mind the Buzzcocks. He appeared in two of Bailey's live shows; with Phil Whelans in Bill Bailey's Cosmic Jam (1996) as part of the band "The Stan Ellis Experiment", and in Part Troll (2004) with Kevin Eldon and John Moloney in Kraftwerk spoof, "Das Hokey Kokey". He also appears on Bailey's Bewilderness DVD in the spoof interview Legacy of Dreams: With Martin Trenaman. Along with Bill Bailey, Phil Whelans, and Kevin Eldon, he is a member of the punk rock cover band Beergut 100.
