Having finished in Blackrock, he went to University College Dublin and in 1998 he was a member of the Ireland U19 side that won the FIRA World Youth Championship. That side was coached by Declan Kidney and once again O'Driscoll's midfield partner was Shane Moore who also captained the side.
In February 1999 he made his Ireland Under-21 debut in the 24-9 victory over France, in a squad that was captained by Leo Cullen and included, Geordan Murphy, Peter Stringer, Marcus Horan, current Leinster captain, Peter Smyth, Mick O'Driscoll, Bob Casey, Donncha O'Callaghan and Jeremy Staunton. In April of that year, he was called into the Ireland Senior squad for the first time for the game against Italy. He didn't play that day but kept his place in the squad for the summer tour to Australia when he won his first cap playing against the Wallabies on the 10th June '99. He won his second cap against the same opposition a week later.
During the 1999/00 season he played in the World Cup warm-up game against Argentina at Lansdowne Road and in the tournament itself he played a part in all four of Ireland's games, scoring his first international try in the 53-8 victory over the United States.
A regular in the side during the 2000 Five Nations, he scored tries in the wins over Scotland and Italy and contributed three in the historic 27-25 victory against France in the Stade de France. Injury forced him to miss the summer tour to the Americas.
In the summer of 2001 he was selected for the Lions and was one of the outstanding performers during that campaign, playing in all three tests against Australia.
He scored another hat-trick of tries against Scotland last March and repeated that feat in Ireland's opening game (v Divisional XV) of their 2002 summer tour of New Zealand and scored a drop goal in both Tests v the All Blacks.
On the day that he will win his 31st cap, Brian O'Driscoll will lead the Irish national side for the first time. To date he has scored 89, points, 16 tries and 3 drop-goals.
International Record: 1999: A(1,2), Arg. World Cup: US, A, R(r), Arg.