Adams became manager of Ross County in 2007, winning promotion from the Scottish Second Division in his first season, before reaching the Scottish Cup Final two years later. He joined Hibernian as assistant manager in 2010 before returning to Ross County the following year, where he won the Scottish First Division and was voted PFA Scotland Manager of the Year for the 2011–12 season. Having left County in 2014, Adams became manager of Plymouth Argyle in June 2015.
Adams started his professional career with Aberdeen, but failed to make a first-team appearance. He moved to English side Burnley, making a couple of league appearances in the mid-1990s before returning to Scotland with Ross County in 1996.
Adams was transferred to Motherwell in a deal worth £200,000 in 1998 and spent six years at Fir Park, including a short loan spell with Ayr United. Adams was one of a number of players affected by the club's administration problems, accepting a pay cut in April 2002. Adams failed to win any trophies during his time with Well, although he scored in the 2002–03 Scottish Cup semi-final defeat against Rangers. In 2004, Adams agreed a pre-contract move to his home town club Aberdeen, spending a year at Pittodrie before being transfer-listed and leaving for Livingston in 2005.
In 2006, Adams returned to Ross County as player–coach. In November 2007, Adams was promoted to the role of player–manager, having served as caretaker manager since October. Despite the terms of Adams' appointment, his last playing appearance was in October 2007. He led Ross County to the Scottish Second Division championship in 2008, earning promotion to the First Division. Adams at the age of 33 became the holder of the UEFA Pro Licence which is the highest coaching badge in the senior game. Adams aged 34 then led Ross County to the 2010 Scottish Cup Final, causing upset victories over SPL sides Hibernian and Celtic. County lost 3–0 to Dundee United in the Final.
Adams left Ross County on 11 November 2010 to join Hibernian as assistant manager to Colin Calderwood. Adams has had several disciplinary cases considered by the Scottish Football Association during his coaching career. At one point he was due to be banned for a number of matches, but he won an appeal against part of the suspension. Adams was then suspended for further matches, a sanction which Hibs appealed against. While this appeal was ongoing, Adams described the whole disciplinary process as distressing.
Adams left Hibernian on 19 May 2011 to return to Ross County as manager. In his first season back at County, Adams guided the club to the 2011–12 Scottish First Division championship and promotion to the Scottish Premier League. County clinched the championship with five games to spare. They went on a remarkable 34 game unbeaten run and finished 24 points above 2nd placed Dundee. Adams was elected PFA Scotland Manager of the Year for the 2011–12 season.
Before the 2012-13 season, Adams made seven signings, all of which were free agents. After three draw and one win, Adams was named SPL manager of the month for August. The club's 40-match unbeaten league was ended by a 2–1 defeat to St Johnstone; Adams said he was very proud of achieving such a long run without defeat. In November 2012, Adams appointed Neale Cooper, who had just left Hartlepool United, as his assistant manager. Ross County struggled during the autumn of 2012, but Adams expected the club to avoid relegation. In late-December the club began a winning streak, that eventually led to a top-six finish in 5th position and 1 point off a European position in their first season in the top flight.In the January 2013 transfer window, Adams offloaded nine players and made six new signings. The winning streak continued, which resulted Adams receiving manager of the month awards for January and February. During the season, Adams was linked with positions at Dundee United and Aberdeen. Adams was nominated for PFA Scotland Manager of the Year, but lost out to Allan Johnston. At the end of the 2012-13 season, Adams signed a new contract with the club.
Ross County finished 7th under Adams at the end of the 2013–14 Scottish Premiership season, the second season in a row finishing above Hibernian, Hearts, Kilmarnock, Partick Thistle and St Mirren.
Following a 2-1 Scottish League Cup win over Stranraer, Adams left Ross County on 28 August 2014.
Derek Adams was appointed Plymouth Argyle manager on 11 June 2015. In his first season in English football as a Manager he guided Plymouth Argyle FC to the League 2 Play Off Final at Wembley for the first time in 20 years, the following season guided them to a 2nd place finish and promotion to league 1 just missing out on top place by the last game .Ross County
Scottish Challenge Cup: 1
Scottish First Division (1): 2011-2012
Scottish Second Division (1): 2007-2008
Football League Two promotion (1) : 2016-17
PFA Scotland Manager of the Year for the 2011–12 season.
As of match played 16 September 2017