Chapman"s first published work was Jazztown, released in 1991 by Raven Arts Press. This was followed five years later by The New Pornography, a collection of poems described as "darkly humorous" by The Irish Times. His story collection, The Wow Signal (Bluechrome Publishing ) was published in 2007.
He also wrote the Doctor Who audio drama, "Fear of the Daleks" (Big Finish, 2007).
Based on his own published story of the same name, he wrote the short drama film Burning The Bed, which starred Gina McKee and Aidan Gillen. Burning The Bed was a prizewinner at the 2004 Worldfest film festival in Houston, Texas and was also named Best Narrative Short at the DeadCENTER Festival in Oklahoma City, Oklahoma.
Chapman has also written five episodes of the children"s television series, Garth and Bev, for Kavaleer Productions. This aired on RTÉ in 2009 and Cbeebies in 2010, and has worldwide distribution.