He then played in England with Wolverhampton Wanderers before returning to Scotland, finishing his career with spells at Aberdeen, Falkirk and Partick Thistle.

[9] He featured regularly in the Celtic first eleven until the arrival of Martin O'Neill in the 2000–01 season saw him become more of a fringe player,[7] although he did score the opening goal in the 2001 Scottish Cup Final, a 3–0 win over Hibernian at Hampden Park.

[11] McNamara re-established himself in the team in 2003–04[7] and was awarded the SFWA Footballer of the Year in 2004, beating off competition from his teammates Henrik Larsson and Chris Sutton.

After he had accepted the Wolves offer, McNamara felt that Celtic showed a lack of respect to him in their comments to the media and he accused them of harming his reputation for their own benefit.

[18] After a promising start to his Wolves career, the player sustained a cruciate knee ligament injury in the home match with Leicester City in September 2005.

[20] McNamara joined Aberdeen from Wolves on a two-year contract in May 2007,[21] but he left Pittodrie before the end of the season, with manager Jimmy Calderwood citing "travelling and injuries" as the reasons for his departure.

[24] McNamara signed a one-month loan deal with Partick Thistle in February 2010, making him available to debut the following day against Dundee if selected.

[25] The terms of the deal allowed it to be extended beyond its initial period, but McNamara suffered a leg break during a match against Ayr United, prematurely ending his 2009–10 season.

[28] McNamara made his debut for the Scotland national under-21 team in a 2–1 away win over Greece on 13 December 1994, in a 1996 UEFA European Under-21 Championship qualifier.

[32][33] McNamara began his managerial career at Partick Thistle where he was appointed caretaker manager on 15 April 2011, after Ian McCall left his job.

[35] Thistle performed well in his second season as manager, reaching the Challenge Cup final and lying in second place in the First Division in late January 2013.

[40] McNamara's first full season at Tannadice saw United reach the Scottish Cup Final, which his side lost 2–0 to St Johnstone.

[43] Reports following Dundee United's 2–1 defeat to St Johnstone on 26 September 2015 suggested McNamara had been relieved of his duties,[44][45] which was confirmed by the club two days later.

[46] McNamara was appointed manager of League Two club York City on 4 November 2015,[47] and his first match in charge came three days later, with a 3–2 away defeat to Accrington Stanley in the FA Cup first round.

[50] Following talks between McNamara and the club, York announced the manager would resign if they failed to gain a "positive result" in their next match, against Braintree Town.

[56] McNamara was taken to the intensive care unit of Hull Royal Infirmary in February 2020, after he collapsed near his home in York, having suffered a brain hemorrhage.