Arsenal Lansbury was born in
Enfield,
Greater London and grew up in
Potters Bar. In 1999, he joined
Arsenal as a schoolboy from the books of
Norwich City. As such Lansbury featured as a regular for the club's academy sides. He finally made his first-team debut on 31 October 2007, in Arsenal's 3–0 League Cup win over
Sheffield United, when he was brought on to replace
Theo Walcott in the 83rd minute. Lansbury missed the second half of the 2007–08 season due to
glandular fever but returned to fitness in time to participate in pre-season training and the 2008 pre-season friendly games. He was described by former Arsenal striker
Alan Smith as having "huge potential". On 1 July 2008 he signed his first professional contract with Arsenal. but was restricted to cup games at the club. On 31 January 2009, Lansbury went on
loan to
Scunthorpe United in
League One for a month. He scored on his full debut against
Swindon Town in the league, adding three further goals during his loan campaign. Lansbury featured in the
FA Youth Cup Final for Arsenal, helping them win the trophy over
Liverpool, assisting
Gilles Sunu on the first goal and
Jay Emmanuel-Thomas on the fourth goal in the first leg 4–1 victory. On 21 August 2009, Lansbury joined
Watford on loan until 31 December 2009. He scored his first goals for them with a brace against Sheffield Wednesday on 23 October 2009. On 31 December 2009, Lansbury signed a new long-term contract with Arsenal. After signing a new deal, manager Arsène Wenger said that Lansbury "will be a big player". He made his Premier League debut for Arsenal on 9 May 2010 against Fulham on the last day of the season, after returning from his loan spell at Watford. Arsenal won the match 4–0. His first goal for the club came against
Tottenham Hotspur in the 3rd round of the
League Cup, on 21 September 2010. Lansbury played the full 90 minutes and 30 minutes extra time, as the Gunners ran out 4–1 winners against their bitter
North London rivals. It was a goal which he said was like a dream. After impressing against Spurs, Lansbury went on to be named in the Arsenal squad for their
UEFA Champions League game against
Shakhtar Donetsk but did not make an appearance off the bench. After a successful loan spell at Norwich City for much of the 2010–11 season, making 23 appearances and being involved in nine goals, he returned to his parent club. He made two substitute appearances for Arsenal at the beginning of the season before joining
West Ham United at the end of August 2011 on a season long loan for rest of the 2011–12 season. On 13 September 2011, Lansbury signed a contract extension, for an undisclosed period of time, with Arsenal.
Loan to Norwich City On 22 November 2010, Lansbury joined Norwich City on a 28-day emergency loan deal to cover for injuries in the City squad. He was given the number 12 shirt and made his debut in the
East Anglian derby victory against
Ipswich Town on 28 November, setting up a goal for
Grant Holt in the process. Lansbury sustained a hamstring injury in the 2–1 away victory over
Coventry City. After briefly returning to Arsenal in mid-January, he soon rejoined Norwich on loan until the end of the season. He scored his first two goals for the club in consecutive home games against
Millwall and
Reading – the former being a stoppage time winner. He became a cult hero after his goal against
Leeds United when he celebrated by doing the Dougie made famous by the song
Teach Me How to Dougie. Lansbury missed out on the 2010–11 Football League Championship Young Player of the Year award after fierce competition from
Connor Wickham who at the time was playing for
Ipswich Town.
Loan to West Ham United in 2011 On 31 August 2011, Lansbury joined
West Ham United on a season-long loan from Arsenal. He made his debut on 10 September 2011 in a 4–3 home win against
Portsmouth scoring West Ham's second goal, eventually finishing with the Man of the Match accolade. In October 2011, Lansbury was ruled out until Christmas with a knee injury. On 21 February 2012, Lansbury was brought on to play in goal against
Blackpool after
Robert Green had been sent off for a
professional foul with West Ham leading 2–1. Manager
Sam Allardyce had not named a goalkeeper amongst his substitutes. West Ham went on to win the game 4–1, and fans chanted "England's Number 1" at the final whistle in tribute to Lansbury's second-half goalkeeping debut, keeping a clean-sheet in the process. West Ham's travelling
fans also sang 'Are you Ludo (Hammers favourite
Ludek Miklosko) in disguise?' to Lansbury in honour of his emergency shot-stopping stint between the sticks. Lansbury, with West Ham, won the
2012 Football League Championship play-off final, in a 2–1 beating of
Blackpool at
Wembley Stadium, a triumph that earned the Irons promotion back to the
Premier League, where the club remain.
Nottingham Forest in 2014 On 28 August 2012, Lansbury joined
Football League Championship side
Nottingham Forest from Arsenal on a four-year deal for a transfer fee believed to be in excess of £1 million. On 19 February 2013 he scored his first goal for the club by netting the fifth goal in a 6–1 victory over
Huddersfield Town. Lansbury scored the first goal of Forest's 2013–14 campaign in the Championship, netting the only goal in a 1–0 victory over Huddersfield Town. Lansbury scored his second goal on his third appearance of the season, in a 3–0 win over
Bolton Wanderers. Having established himself as a regular starter for Forest, Lansbury missed the final months of the
2013–14 season through injury and was strongly linked in the summer with a move to newly promoted
Premier League side
Burnley. However, Lansbury signed a new three-year contract with Forest on 22 August 2014. He made his return from injury on 26 August 2014, scoring and winning the fan's man of the match award in a 2–0
League Cup second round victory over
Huddersfield Town. Lansbury then started Forest's next game in the
Championship away at
Sheffield Wednesday. He played 68 minutes of the game and scored Forest's winner in the thirty-seventh minute. Lansbury also went on to win the
EFL Championship Player of the Month award of February 2015. Prior to and during the 2015–16
Championship season, Lansbury was once again linked with a transfer to Burnley. Despite the continued media speculation and negotiations between Forest and Burnley, Lansbury's manager
Dougie Freedman praised his new captain's attitude and commented that his performance against
Rotherham was a "delight to watch". Less than a week after the Rotherham game, a statement was released by
Forest on 20 August 2015 confirming that Lansbury had declared his intention to stay at the club. {{quote box|width=30em|quote="His commitment is not in question. That is why he is still the captain, because he plays with commitment for this side. He has always done that. I am sure that will not change. He is a very good player for us; he has been very good for us in the last few games. He has a good mentality; one that is an example to the rest of the squad." Lansbury continued to be a first-team regular during the
2016–17 season under the new management of
Philippe Montanier, and scored his first career hat-trick on 25 November 2016 to inspire Forest to a 5–2 defeat of
Barnsley at
Oakwell. After the game Montanier stressed the importance of successfully negotiating a new deal for Lansbury, whose contract was due to expire in the summer of 2017. On 9 December Lansbury was awarded the Championship Player of the Month Award for November, being the second time that he's won such. His outstanding performance in Forest's win over Barnsley was cited as a factor in him being bestowed with the honour by Sky Sports pundit
Don Goodman. In January 2017, and with his contract situation unresolved, Lansbury was the subject of bids from
Derby County and
Aston Villa, the latter of which was reported to be worth £3 million. Amid the speculation, Lansbury missed Forest's
FA Cup defeat at
Wigan Athletic on 7 January because his "head was not right to play". On 20 January, after reported interest from
Watford,
Celtic and
Norwich City, Lansbury completed a transfer to Aston Villa to bring an end to his four-and-a-half-year stay at Forest.
Aston Villa Lansbury signed for
Aston Villa on 20 January 2017 for a reported fee of £3 million. He scored his first goal for the Villans against Leeds United
on 1 December 2017 to earn his side a 1–1 draw. However, from the beginning of the
2018-19 EFL Championship campaign onwards, Lansbury found it difficult to find regular game time, playing mostly in cup competitions. At the start of the
2020–21 Premier League season, Lansbury found himself behind
John McGinn,
Conor Hourihane and
Jacob Ramsey in the pecking order. On 15 September 2020, he made his 50th appearance for Aston Villa, after years with the club, in a 3–1 away victory over
Burton Albion in the
EFL Cup.
On 20 October 2020, Aston Villa confirmed their squad for the 2020-21 Premier League season, which did not include Lansbury. On 29 January 2021, Lansbury departed
Aston Villa after agreeing a mutual termination of his contract.
Bristol City On 29 January 2021, Lansbury joined
Championship side
Bristol City on a short-term contract until the end of the 2020–21 season. Lansbury made his Bristol City debut on 6 February, in a 2–0 home league defeat to
Cardiff City.
Luton Town On 14 May 2021, Lansbury left Bristol City following the expiration of his contract and was then immediately signed by
Luton Town. In June 2023, Luton confirmed that Lansbury would be leaving the club at the end of the
2022–23 season. Lansbury announced his retirement from professional football on 17 August 2023, at the age of 32. ==International career==