Born in Derry, Northern Ireland, he began his club career with Institute before joining Manchester United, for whom he made his professional debut in 2005.

[1] A former pupil of St Columb's College, he played junior football in the Derry and District League, and then with Institute before joining Manchester United in 2004.

[8] He made his senior debut for United on 26 October 2005 in a League Cup match against Barnet, coming on as a substitute for Lee Martin.

In December 2008, he travelled with the United squad to the 2008 FIFA Club World Cup in Japan, where, despite not making any appearances, he picked up a winners' medal.

[15] Gibson was one of a number of young United players who came under criticism when they lost a four-year unbeaten home record in Europe, losing 1–0 to Beşiktaş at Old Trafford.

[19] In February 2011, Gibson's national team manager, Giovanni Trapattoni, told him that he must leave Manchester United in order to further his career.

[25][26] He became the fourth ex-United player to sign for Everton under David Moyes, following Phil Neville, Tim Howard and Louis Saha.

[31] Gibson was sent off for the first time in his career, in a 2–1 win away to West Ham United on 22 December 2012,[32] although the red card and subsequent ban were rescinded by The Football Association five days later.

[34] Gibson only made one league appearance during the 2013–14 season as it was ended in October when he suffered serious cruciate knee ligament damage whilst on international duty.

[36] He made his debut on 4 February as a 52nd-minute substitute for Jack Rodwell in a 4–0 win at Crystal Palace,[37] and totalled 12 appearances as the Black Cats suffered relegation to the Championship.

[43] He made his debut for the club on 19 February in a Football League Trophy semi-final victory over Newport County, playing the full match and scoring one of the penalties in the shoot-out.

[54] In 2007, Gibson was included in several senior Republic of Ireland squads for Euro 2008 qualifiers,[55] before he eventually made his debut in a 4–0 win against Denmark.

In the 54th minute, Gibson fired a shot from outside the penalty area that the Danish keeper, Jesper Christiansen, could only palm away, allowing Shane Long to follow up and score the Republic's third goal.

Manager Giovanni Trapattoni also cited Gibson's confidence on the football pitch as the reason for choosing him ahead of Liam Miller and Andy Reid.

[59] On 8 February 2011, Gibson scored his first goal for his country, a shot from long range in a 3–0 victory over Wales in the first match of the 2011 Nations Cup.

[62] On 30 September 2013, Gibson was recalled to the Republic of Ireland squad for the World Cup qualifiers against Germany and Kazakhstan by interim manager Noel King.

[64] On 3 September 2014, Gibson made a start for the Republic of Ireland after recovering from his long term knee injury when his team beat Oman 2–0.

On 11 October, he made his first competitive appearance for Ireland in more than a year, playing the full 90 minutes in the team's 7–0 UEFA Euro 2016 qualification defeat of Gibraltar.