Mark has exhibited at such places as the Mall Galleries, the Royal Academy of Arts, the Royal Ulster Academy and the National Gallery of Ireland. Additionally, his paintings have featured in international events as the Florence Biennale of Contemporary Art, Galerie Brusberg in Berlin, and the Basel Art Fair in Switzerland. Mark has participated several times in the BP Portrait Award and the Hunting Art Prize Exhibition at the Royal College of Art. His works can be found in numerous collections including the Arts Council for Northern Ireland, the Ulster Television Collection, the National Self-Portrait Collection of Ireland, as well as many private collections in both the U.K and abroad, and his commissioned portrait of the Prince of Wales hangs in the headquarters of the Royal Gurka Regiment.