Mark made his Senior debut for Ireland at the Moscow Chess Olympiad in 1994 and has competed in seven Chess Olympiads to date: Moscow (1994), Yerevan (1996), Istanbul (2000), Bled (2002), Calvia (2004), Turin (2006) and Dresden (2008). He also played board 1 for Ireland at the European Team Chess Championships in Leon, Spain in 2001. Mark was ranked number 1 in Ireland at the age of 17. He was awarded the title of International Master of Chess at the FIDE Congress during the Istanbul Olympiad in 2000. Mark gained the title of FIDE Trainer in April 2020. As of September 2022, Mark is the Number 8 ranked active Irish player on the International FIDE rating list.