Cotterill and Forest part company
Nottingham Forest have confirmed Steve Cotteril has "departed the club with immediate effect" after a meeting with the club's new owners.
The Kuwaiti-based Al-Hasawi family assumed control of the Championship club on Tuesday, and have wasted little time in implementing their plans for the Reds.
Cotterill leaves just nine months into the three-and-a-half-year deal he signed when replacing former England head coach Steve McClaren in October.
A club statement issued on Thursday morning read: "Nottingham Forest can confirm that manager Steve Cotterill has departed the club with immediate effect.
"Mr Cotterill met with the club's new owners, the Al-Hasawi family, yesterday and after long deliberations they have decided to make a new appointment in a bid to deliver their long-term vision.
"The club would like to acknowledge their gratitude to Mr Cotterill for guiding it through an extremely difficult and traumatic period and for retaining the side's Championship status last season.
"The club will be making no further comment at this time."
Cotterill left Portsmouth to take over at the City Ground on October 14 after a compensation package was agreed with Forest's fellow Championship strugglers.
The Reds were 21st in the table when he arrived and battled against relegation for the remainder of the campaign, with Cotterill eventually securing survival and a 19th-place finish.
The former Cheltenham and Notts County boss had to contend with crippling financial constraints during his tenure, as well as the death of the club's owner Nigel Doughty in February.
The Al-Hasawi family took control of Forest this week after reaching terms to buy the controlling stake left by Doughty.
Former Tottenham boss Harry Redknapp has emerged as one of the bookies' favourites to fill the vacancy.
A number of other names have already been linked with the job, including former Birmingham boss Alex McLeish, ex-Wolves manager Mick McCarthy, Peterborough's Darren Ferguson and former Forest player Roy Keane.
The Al-Hasawi family have stated their intent to restore Forest to its former glories, targeting a return to the Premier League.
McLeish, McCarthy and Keane all have experience of winning promotion from the Championship, while Ferguson has achieved three promotions in the lower echelons of the Football League during his two spells at London Road.