In February 2001, Norwich appointed their first youth team coach for 15 years when they announced Adrian Boothroyd would replace Keith Webb. 30 year old Adrian joined from Peterborough where he had been Assistant Academy Director under Kit Carson. Despite his young age, Adrian already held an UEFA A class coaching certificate. Adrian joined Peterborough as a player from Manfield. Earlier in his career, he had played for Bristol Rovers, Hudderfield and Hearts.

In October 2003, he surprised the Canaries by quitting their successful Academy (Ryan Jarvis, Ian Henderson, Dean Sinclair, Jason Shackell, Joe Lewis etc) to take over as Youth Development Manager at West Bromwich Albion - made all the more surprising by the fact that WBA did not have Academy status. Sammy Morgan took over the management of the day-to-day coaching of Norwich's Under-19s in the interim period

He quit the Baggies for Leeds United in July 2004 when he was offered the chance to join Kevin Blackwell's first team coaching squad.

On 29th March 2005, Watford surprisingly named Boothroyd as successor to manager Ray Lewington who had been sacked the previous week. he signed a 12month rolling contract. Experienced Keith Burkinshaw, the former Tottenham and West Brom boss, was named Boothroyd's number two. Boothroyd, who included Hornets former joint stand-in boss Nigel Gibbs and reserve team manager David Hockaday in his back-room staff, said: "I've been working for this moment for a long time. I'm absolutely delighted - I have fallen on my feet." Watford chairman Graham Simpson said: "The board were unanimous in
recognising Adrian's potential to become a great new, young manager." Boothroyd has departed Elland Road with the blessing of manager Kevin
Blackwell. He said: "I would never stand in Adrian's way when it comes to taking up a managerial vacancy. He has been a very valuable member of the coaching staff and we will all miss the experience he brought to his job and his jovial character."

Watford's impressive 2005/6 campaign saw Adrian linked by many papers on 11th December 2005 with the managerial vacancy at Southampton following Harry Redknapp's resignation and return to Portsmouth. Instead, Adrian signed a four year contract with the Hornets and led them to the Championship play-offs where they defeated Crystal Palace in the semi-finals before beating Leeds 3-0 at the Millennium Stadium in Cardiff, to win a place in the Premiership.

In March 2007, The Sun suggested that Boothroyd might take over running the England Under-21 team from Man City's Stuart Pearce.

Despite Watford's relegation back into the Championship at the end of the 2006/7 season, Aidy was awarded an extension to his contract until 2010.

Boothroyd left Watford on 3rd November 2008 by mutual consent with the club then in 21st place in the Championship. Watford's chairman Graham Simpson said "Both parties feel his tenure at the club is simply at an end. We have mutually decided that a parting of the ways is in the best interests of all concerned." Malky Mackay was appointed as caretaker manager with Martin Hunter assisting.

Simpson told BBC Three Counties Radio: "I think he's done a fabulous job. But I think with all managers, especially younger ones, sometimes they need a break. It's a very intense business to be involved in. I think he did a great job initially. To get us into the Premiership on our wage bill as he did was phenomenal. I don't think there's any disgrace for someone to say 'I've done three or four years and I need a break'. Perhaps a break isn't such a bad idea. You can take a look and see all the good things you have done and perhaps the things you need to learn from and you come again. I believe Aidy will definitely come again as a manager."

Boothroyd was later linked with vacancies at Swindon and Leeds. He was quickly installed as the Bookies' favourtie to take charge at Carrow Road following the sacking of Glenn Roeder on 14th January 2009. In June 2009, Aidy expressed his interest in the managerial vacancy at Swansea created when Roberto Martinez joined Wigan to replace Sunderland-bound Steve Bruce.

He was appointed as Colchester manager on 2nd September 2009, succeeding Paul Lambert who had joined Norwich. Boothroyd said "The club is progressive, it's not on a downward, it's on an up and it wants to go forward. That's what I want to do, I think there's a real chance of getting some momentum and getting some success here and I want to be a part of it. After meeting [chairman] Robbie Cowling and his board, straight away I got excited about it and I put that at the forefront of my mind, because the guy you work with is important,"

On 20th May 2010, Aidy took over as Coventry boss replacing the sacked Chris Coleman. He signed a three year deal with compensation going to Colchester United. Aidy said "This is a big club and a big challenge but is one I am very much looking forward to. The potential is here - from the financial stability to the magnificent Ricoh Arena - and I am very much looking forward to getting on with the job."

Boothroyd, and Assistant Manager Martyn Pert, was sacked as Coventry manager on 14th March 2011 following a run of only one victory in fourteen games that left the Sky Blues just seven points of the relegation zone. First-team coach Steve Harrison and chief scout Andy Thorn were put in temporary charge. Boothroyd revealed his frustration at being relieved of his duties: "I am deeply disappointed to be leaving Coventry City and to be the ninth manager dismissed from the club in 10 years. Last Christmas I took the club to its highest league position for several years and, since then, we have had to endure a period of injuries and suspensions to seven key players, during which time we have played most of the top teams in the league.It is a shame that I have not been given the chance to take the club back up the league table where we were at the turn of the year."

On 30th November 2011, Aidy was appointed manager of League Two strugglers Northampton Town, who had sacked Gary Johnson and whose caretaker managers Dave Lee and Tim Flowers had seen the Cobblers lose 7-2 and 4-0 and were three points above the relegation zone. Former Swindon boss Andy King was appointed as his assistant

Boothroyd was sacked as Northampton manager on 21st December 2013 after a defeat to Wycombe left the Cobblers at the bottom of League Two.

He was appointed manager of England's Under-20 team. Boothroyd was appointed interim England Under-21 manager in September 2016 folllwoing Gareth Southgate's promotion to the national team when Sam Allardyce resigned.

On 3rd February 2017, he was confirmed as the England Under-21 manager. he had secured qualification for this summer's finals in Poland. Boothroyd commented "I've been at the FA three years; this is the logical next step.I believe I am here on merit because I've worked in all four divisions and I've got an understanding of speaking to a League Two manager or a Premier League manager and the problems they have."

Following a disappointing Under-21 European Championships in 2021, Boothroyd left his position on 16th April 2021. The Young Lions failed to exit their group.

On 17th May 2022 he was drafted in to head with coaching the Northern Ireland international team due to Adam Sadler's unavailability. Northern Ireland manager Ian Barraclough said "I delved into the contacts book and Aidy is someone who I've known for a number of years. I used to play with him at Mansfield Town in the early 1990s.He's got a wealth of experience. He's been a Premier League coach, a Premier League manager, worked within academies at Premier League clubs and also worked internationally for seven years with England's U21s, U20s and U19s.To call on someone like him has been invaluable. He'll go to the June games with us and we're totally looking forward to it."