Henri Lansbury was with Norwich until the age of 9 when he followed Roy Massey to Arsenal. By the tme he was 14, he was training with Arsenal's Under-18s and is seen as one of their brightest prospects. A central midfielder, Henri played for England in the UEFA Under-17 competition held in May but was injured in the semi-final win over France and so missed the final which England won

Lansbury made his first team debut for Arsenal in the autumn of 2008 in the 3-0 Carling Cup victory over Sheffield United.

On Transfer Deadline Day (2nd February 2009), Henri was loaned out to Scunthorpe. He helped them to win promotion to the Championshp and reach the final of the Johnstone Paint Trophy

Lansbury then competed for England in the European Under-19 championship; and reached the final before losing 2-0 to hosts Ukraine. Scunthorpe manager Nigel Adkins then expressed his interest in having Lansbury return to Scunthorpe.

On 1st September 2009, Henri was loaned to Malky Mackay's Watford until 31st December 2009. This was extended until the end of the season. Henri made 37 appearances for Watford, scoring five goals.

On his return to Arsenal, he made his Premier League debut in the 4-0 thumping of Fulham on 9th May 2010.

During 2010/11 his Arsenal appearances have been restricted to the Carling Cup, although his last outing brought him a goal in the 4-1 North London derby win over Tottenham at White Hart Lane in September.

His made his full debut for England Under-21s in Germany in November 2010 – and played the final 32 minutes of a 2-0 defeat as an emergency goalkeeper after substitute Jason Steele, who had replaced Scott Loach, had been sent off

On 22nd November 2010, he joined Norwich on a month's loan as cover for the injured Korey Smith, Matthew Gill and Stephen Hughes

Lansbury made his debut for City on 28th November 2010 in the Old Farm derby clash with Ipswich which the Canaries won 4-1. Lansbury had an impressive game and was involved in the second of Grant Holt's three goals. Lansbury's spell at Carrow Road was then extended until 16th January 2011

Lansbury returned to Arsenal in mid-January having made 5 appearances for Norwich. A hamstring injury sustained against Coventry denied him further appearances. He returned to Norwich on 21st January 2011, signing on loan until the end of the season

On 20th March 2011 Lansbury came runner-up to Ipswich's Connor Wickham in the Young Player of the Year at the Football League Awards

Norwich won promotion to the Premiership, on 2nd May 2011 with a 1-0 win at Portsmouth with Henri playing a key role (23 appearances, 4 goals) in the Canaries' promotion challenge.

Linked in July 2011 with a switch to Bolton as a makeweight in Arsenal's bid for defender Gary Cahill, Norwich reportedly made a £1.5million bid for him. Despite being linked with QPR, Norwich and Blackburn in the August 2011 transfer window, Henri was loaned to West Ham on 31st August 2011 days after appearing as a substitute for the Gunners in their 8-2 defeat at Manchester United. Henri will stay with the Hammers until the end of the 2011/12 season. He made 22 appearances for the Hammers

On 28th August 2012, lansbury signed for Notts Forest for £1million, signing a four year contract and becoming manager Sean O'Driscoll's ninth signing of the summer. He had played just eight games for Arsenal.