Gaffney will operate as the backs coach for the Ireland team, combining his coaching position that he has taken with Leinster Rugby.
Tainton, who was a member of the Ireland coaching staff from 2003 up until the end of the 2008 RBS Six Nations championship, returns to the set-up as kicking coach.
Commenting on the announcement, Ireland coach Declan Kidney said: "We are delighted to have both Alan and Mark on board with Ireland. Both of them are extremely strong technical coaches in their areas and so I think they will bring a further positive mix to the coaching team and squad.
"Alan brings with him experience of both international and most importantly Irish rugby. Mark is recognised as one of the top kicking coaches in the world and his experience of working with the squad in the past will help with the transition over the next number of weeks."
Gaffney is a life member of the famous Randwick rugby club in Sydney and served as their coach since 1984.
During that period, Gaffney held various roles including coach of the New South Wales Under-21s and New South Wales Waratahs as assistant to present Ulster coach Matt Williams (1997-1999) from where he joined Leinster, again as assistant to Williams.
During that time, Leinster won the Celtic League in 2001/02 and were quarter-finalists in the Heineken Cup the same season.
With current Ireland coach Kidney moving on from Munster to Ireland in 2002, Gaffney took up the reigns and in his three seasons with the province, they won the Celtic League, Celtic Cup and were twice semi-finalists in the Heineken Cup.
In the summer of 2005, he took the position of backs coach of Australia, leaving them later that year to coach Saracens in the Guinness Premiership. Last season he led Sarries to the semi-finals of the Heineken Cup.
Mark Tainton is a former Bristol out-half who was capped at both England 'A' and Under-23 levels in his career, during which he scored over 3,000 points.
After his retirement from competitive rugby in 1997, he was appointed kicking coach for the England tour to Argentina that summer.
He moved further into coaching and was head coach for Richmond Rugby in the English Premiership from 1997-1999.
Following that, he was appointed director of rugby for Oxford University from 1999 to 2002, winning three varsity games.
Throughout his coaching career he continued to deliver his considerable kicking expertise on a consultancy basis and began working with Munster in 2002, following which he joined the Ireland squad and worked with them until the end of this year's Six Nations.
Ireland Coaching Staff Profiles