He scored an outstanding try in Wales U19's win over France U19's in the 2005-06 Grand Slam decider – and played a part in the newly created team's Six Nations Under 20s Championship in 2007.
He scored a try in the Plate quarter-final clash against Italy in Hong Kong; his team ultimately won the trophy by overcoming Argentina in the final.
He was one of only 5 players (his twin brother Robert was another) who were part of the London Welsh squads that won the Greene King IPA Championship in 2011-2012 and again in 2013-2014 and he played throughout both the club's seasons in the Aviva Premiership.
In season 2015 - 2016 he scored a hat-trick of tries to help London Welsh beat Yorkshire Carnegie 33 - 10 at Headingley in April to win the British & Irish Cup and was awarded Man of the Match.
Following the unfortunate financial situation at London Welsh and its loss of a licence to continue to play in the RFU Greene King Championship, James returned to Ebbw Vale RFC in January 2017.