On 18th Auguist 2009, Norwich City chief executive David McNally announced that Paul Lambert had left Colchester United to take charge at Norwich City on a rolling year contract. Lambert replaced Bryan Gunn who was sacked on 14th August 2009; partly due to a 7-1 home defeat to Lambert's Colchester United. Lambert brought with him assistant Ian Culverhouse and and football operations manager Gary Karsa

As a player, Lambert started at at Linwood Rangers Boys' Club in 1980, before entering the professional game with St. Mirren in 1985. As a 17 year old in 1987 with St Mirren, Lambert won his first Scottish Cup winner's medal. He played there for eight years before transferring to Motherwell in 1993.

In 1996, Lambert transferred to the German Bundesliga side Borussia Dortmund. He was well liked by the fans in Germany, and he contributed to the team's success in winning the 1997 UEFA Champions League final against Juventus in Munich on 28th May 1997. He became the first British player to win the European Cup with a non UK team, and the first British player to win the Champions League since its inception.

In November 1997, he was signed by Celtic for £2milion. During his time with Celtic, he won four SPL titles, two Scottish Cups, two CIS Insurance Cups and was captain of the side that reached the 2003 UEFA Cup Final in Seville.Whilst at Celtic, he first met David McNally. Lambert was also a Scotland international, winning 40 caps and scoring one goal,

After studying for football coaching qualifications in 2005, Lambert landed his first managerial job with Livingston on 1at June 2005. His tenure ended the following February when he resigned after only winning two league games since starting the job.

Lambert was appointed manager of English-team Wycombe Wanderers on 30 June 2006. He led Wycombe to the League Cup semi-finals after defeating Premier League sides Fulham and Charlton Athletic. The semi-final tie, against then Premier League champions Chelsea, saw Wycombe hold Chelsea to a 1–1 draw at Adams Park before losing the away leg. This was the first time in over 30 years a fourth tier team had reached that stage of the League Cup. He resigned as Wycombe manager on 20th May 2008 On 9th October 2008, he was appointed as manager of Colchester United succeeding Geraint Williams.

Norwich's impressive form under Lambert which saw them rise to top place in League One saw him win Manager of the Month awards for both December 2009 and January 2010 (during which Norwich won 6 games out of 6). Norwich won the League One title, finishing on 95pts and Lambert was named the League One manager of the season

After a tribunal ruled that Norwich had to pay Colchester £425,000 in compensation plus a £75,000 fine, Lambert signed a new contract with Norwich on 1st June 2010, as did assistants Ian Culverhouse and Gary Karsa.

At the end of their first season, Lambert and Culverhouse enabled Norwich to win the League One title.

In January 2011, Burnley made an approach to speak to Lambert following the sacking of Brian Laws. Norwich refused permission and after a tense 24hrs which saw Lambert installed as the bookies' favourtie, he released a statement that "I want to put the speculation to bed - I've never had any intention of going.I've said on numerous occasions that I'm happy here and that's still the case. The players and the fans have been tremendous for us since we joined here and what they have achieved over the last 16 months or so is absolutely phenomenal, as I keep saying. "We've got a job to do here Watford's Malky Mackay was also linked to the Burnley position

On 2nd May 2011, Norwich won promotion to the Premier League with a 1-0 win over Portsmouth

Lambert was named Championship Manager of the Season for 2010/11 on 24th May 2011 and the following day, signed an improved contract with the club which would hopefully extinguish speculation linking him with the managerial vacacny at West Ham.

At the end of February 2012, and with Norwich sitting in eight place in the Premiership, Lambert was voted into Norwich City's Hall of Fame.

Norwich finished twelth in the Premiership and Lambert was made favourite for the vacant manager's role at Aston Villa following the sacking of Alex McLeish on 14th May 2012, a day after Norwich comfortably beat Villa 2-0. The speculation continued and Lambert described speculation he could leave Carrow Road as "absolute nonsense" but on Wednesday 30th May 2012, reports suggested he had offered his resignation following the club's refusal to let him speak to Villa. This wasn't accepted by Norwich but eventually City entered into negotiation with Villa to agree compensation. Lambert was officially named as Villa manager on 2nd June 2012. He became Villa's fourth boss in less than two years. Villa owner Randy Lerner had also held talks with former Manchester United striker Ole Gunnar Solskjaer but he opted to stay at Molde in Norway for family reasons. Villa also spoke with advisors of Wigan boss Roberto Martinez, somebody who had rejected the chance to replace Gerard Houllier 12 months previously.

In October 2012, it was revealed that Lambert was sueing Norwich for breach of contract, seeking between £1.5m and £2m. A Premier League Managers' Arbitration Tribunal will decide on the case in spring 2013 and Lambert has said he will be represented by the League Managers' Association (LMA). However Norwich are also sueing Lambert. This was settled in December 2012 with Norwich paying Lambert a bonus for the 2011/12 season whilst Villa will pay Norwich compensation for signing / poaching City's manager.

Lambert's first season did not proceed well with Villa flirting with the bottom three for the first half of the season. An 8-0 defeat at Chelsea was part of a run of ten games that saw them take just 10 points from 11 games, including home defeats to Wigan and Southampton. A 2-1 defeat to Bradford in the semi-final of the Capital One Cup did not help Lambert's cause with the Villa faithful. Although he signed a new contract with Villa on 17th September 2014, he was sacked on 11th February 2015 - a day after a 2-0 defeat to Hull saw them drop into the Premier League relegation zone. This was the tenth Premier League game without a win and a fifth consecutive defeat. They had also gone 659 minutes without a goal until Jores Okore scored in the 2-1 defeat against Chelsea on 7th February 2015 – the fourth longest in Premier League history. First-team coach, Scott Marshall, and goalkeeping coach, Andy Marshall were placed in temporary charge. It was rumoured that Lambert would be entitled to a £2m or £10m pay-off, depending on which paper you read.

Since leaving Villa the former Champions League winner with Borussia Dortmund went back to his former club to spend time with Jurgen Klopp before his move to Liverpool. He was also on the training ground at Bayern Munich under Pep Guardiola and Real Madrid at the end of last season before ex-Chelsea and AC Milan boss Carlo Ancelotti ended his Champions League-winning reign.

At the beginning of October 2015, Lambert was linked with the managerial vacancy at Sunderland following Dick Advocaat's departure with Sunderland rooted at the bottom of the Premiership.

Lambert was appointed manager of Championship club Blackburn Rovers on 15th November 2015 on a two-and-a-half year deal. He activated a clause in his contract on 28th April 2016 so that he would leave the club at the end of the 2015/16 season. He was linked with the vacancy at Celtic.

On 5th November 2016, Lambert was appointed manager of Wolves. He is the second managerial appointment made by Chinese owners Fosun International since their takeover of Wolves in July. He succeeds Walter Zenga, who was sacked after 14 league games and 87 days in charge at Molineux. Lambert will be joined at Molineux by former Aston Villa development squad coach Stuart Taylor, 41, who will become first-team coach alongside existing first-team coach Rob Edwards.

Lambert left Wolves on 30th May 2017, His role had been in doubt since the end of the Championship season over a dispute about who has the final say on signing players. Lambert wanted to sign British players but agent Jorge Mendes is close to the owners and arranged several of their summer 2016 signings. The decision was made as part of a coaching restructure by Wolves' Chinese owners Fosun following an end-of-season football review. Coaches Rob Edwards, Stuart Taylor and Tony Daley also left the club. Lambert was in charge for 33 matches in all competitions, of which Wolves won 14, lost 14 and drew five.

In June 2017, Lambert was linked with the vacant manager's role at Sunderland. Following Gordon Strachan's departure from the Scotland job "by mutual consent" on 12th October 2017 after they failed to reach the World Cup qualifying play-offs, Lambert was named as a potential replacement along with David Moyes and Alex McLeish. Former internationals Barry Ferguson and Kris Commons both praised and recommended Paul Lambert. Lambert himself said on 15th October that Scotland should have stuck with Strachan and that he had not considered the vacancy.

Following Mark Hughes' sacking as manager of Stoke, and refusals by Martin O'Neill, Gary Rowett and Quique Sanchez Flores to take on the role, Lambert was appointed manager of Stoke City on 15th January 2018. His first game in charge saw them defeat Huddersfield 2-0. Stoke chairman Peter Coates said: "Paul greatly impressed us with his knowledge of our squad and had a clear plan of how he would improve our results. He's a man who backed himself as a player, none more so than when he turned down contract offers in Scotland to go on trial in the German Bundesliga with Borussia Dortmund, and it's obvious he adopts the same approach as a manager." Vice-chairman John Coates added: "Paul has been successful in management at clubs with a strong and stable background and with local ownership - the kind of foundation we are able to give to our managers. We were determined to appoint someone with Premier League experience or an extensive knowledge of English football."

Unfortunately Lambert could not prevent Stoke being relegated to the Championship on 5th May 2018 following a 2-1 home defeat to Crystal Palace. Ahead of that defeat, the statistics told a grim tale. Lambert had been in charge for 14 league games, winning only one, drawing seven and losing six. Stoke have the worst defensive record in the Premier League having conceded 67 goals and the worst goal difference of -34. Stoke and Lambert parted company on 18th May 2018. Stoke said "Whilst he was unable to guide us to safety, it certainly wasn't due to a lack of effort, professionalism and dedication. The club would like to thank Paul for his work over the past four months and wish him well for the future"

Lambert was surprisingly named as manager of Norwich's arch rivals Ipswich Town on 27th October 2018 replacing Paul Hurst who was sacked two days earlier with the Tractor Boys bottom of the Championship with just one win. Lambert signed a contract until the summer of 2021. He is joined by assistant Stuart Taylor, who worked with him at Stoke, while Matt Gill left his role as Norwich's under-23 coach to form part of his backroom team. However "Agent" Lambert was unable to save Ipswich from relegation with the club relegated on 13th April following a 1-1 draw with Birmingham. This put them in the third tier for the first time since 1957.

On 19th December 2020 it was reported that Ipswich Town manager Paul Lambert has tested positive for coronavirus, along with five other members of the League One club's playing and coaching staff. Town released a statement after all members of the first-team squad and coaching staff were tested on Friday morning in response to one player reporting symptoms. His assistant Matt Gill had tested positive earlier in the season which had seen Lambert self-isolating as a close contact whilst waiting for results.

After failing to mount a promotion challenge during the 2020–21 season, Lambert left Ipswich by mutual consent on 28th February 2021, with the club sitting in eighth place in the table. He was replaced by Paul Cook. Lambert had managed 113 Ipswich games with them winning 37, drawing 28 and losing 48.