After two fourth-placed finishes, under the management of Fairclough, Stevenage won The Isthmian League Division Two North in 1990–91, winning 34 of their 42 games, including every match played at home, scoring 122 goals and amassing 107 points.
Fairclough was appointed caretaker manager of Barnet for the final few months of the 2003–04 Conference National season, replacing the popular Martin Allen who had controversially left the North Londoners for Brentford in March 2004.
Although the team had failed to reach the play-off final, Fairclough was handed the job on a permanent basis shortly after by Barnet chairman Tony Kleanthous.
Fairclough's side produced some excellent performances both at Underhill and on the road, including the 3–1 victory over promotion rivals Carlisle United in mid-October, watched by a then-record Conference crowd of 9,215.
Despite this, Fairclough has expressed his disappointment with the season overall, bemoaning his side's failure to draw a "big fish" in the FA Cup which could have seen a sizeable cash injection into the club.
As a result, he signalled his intentions for a squad shake-up in the close season, releasing a number of first team players just days after their final league match.
In April 2010 Fairclough was made caretaker manager at Barnet after the sacking of Ian Hendon, guiding the Bees to safety with a 1–0 win over Rochdale on the last day of the season.
He was made Temporary Manager till the end of the season in early 2011 following the sacking of Mark Stimson however stepped down with 8 games to go and was replaced by Martin Allen.