Matthew completed his Bachelor of Music at the Australian National University School of Music in 1999. Since completing his degree, Matthew has specialised in bass clarinet performance and is the principal bass clarinet of the Canberra Symphony Orchestra. Matthew has performed with the Canberra School of Music Orchestra, the Canberra Chamber Orchestra and the Canberra Choral Society. He excels in theatre performance and has appeared in orchestras for the opera company Stopera and Canberra Philharmonic Society productions including Chicago, West Side Story, Les Miserables, and the Australian premiere of Jekyll and Hyde. He is a founding member of Clarity clarinet quartet, an experienced chamber musician and educator, and a sought after teacher. In 2004 Sergeant O’Keeffe joined the Band of the Royal Military College Duntroon as a clarinet specialist.