As a young boy in Derry, Dermot’s introduction to the fiddle was through his father Joe, and he had classes with local players including Tony Black, Frank McFadden, Paddy McCafferty,  Denis Heaney  and Dinny McLaughlin. Later in the 1980s and 90s he spent much of his time listening to, and learning from Donegal fiddle masters including Con Cassidy, James Byrne, Francie Mooney, Vincent Campbell, and Francie Dearg Ó Beirne. He usually performs solo and unaccompanied. He also teaches at summer schools, masterclasses and other events and prefers to work with small groups or individuals. Dermot especially enjoys the teaching experience and teaches at summer schools, gives master classes and performs at many events.

He played a central role in the establishment of the Irish Traditional Music Archive and spent a number of years as its Chair and he also served as Chair of the selection committee for TG4 Gradam Ceoil. He established Creative Strategic Solutions in 2014 and he works with a wide range of national and local cultural organisations. Prior to that, Dermot played a pivotal role in matters of policy and development  particularly in traditional music through his work with An Chomhairle Ealaíon/The Arts Council and has been involved in national projects including Ealaín na Gaeltachta, Culture Night, Cairdeas na bhFidiléirí and Other Voices.