Dermy comes from Belfast, and learned his early music from local players in Belfast, Antrim and Down, such as Andy Dickson and Gerry McCartney. Later, he and Tara travelled extensively across Ireland, playing and spending time with musicians from many parts of the country, particularly Clare, Cork, Kerry, Donegal and Fermanagh. He was a participant in three Music Network tours, with, amongst others, Dolores Keane, John Faulkner, Paddy Keenan, Maighréad Ní Dhomhnaill, Fintan Vallely, Con Fada Ó Drisceoil and Charlie Harris.He teaches fiddle at the Willie Clancy Summer School along with Bernadette McCarthy.