In those early days, only one or two internationals at most were played there during the season, and it wasn't long before the RFU ground became the headquarters of the Harlequin Football Club.

The North Stand is a temporary structure with an estimated life of 10 years, and is the most recent to be developed for the 2011–12 season.

The corner of the North and Charles Stanley Stand has a memorial for Nick Duncombe who was a promising scrum half for Harlequins and won two caps for England.

The club owns the ground freehold through its subsidiary Harlequin Estates (Twickenham) Limited.

In an interview with the fans website on 23 April 2012, the Chief Executive, David Ellis confirmed that an architect has visited the club and given ideas on possible improvement and further expansion of The Stoop which will be further considered if Harlequins can sell out nine or ten games a season in comparison with the six games sold out in the 2011–12 season.

David Ellis also said there are some immediate concerns for development such as increasing the size of the debenture lounge and the members bar.

[6] On 5 September 2012 Harlequins announced that they had begun a programme of significant investment in upgrading Twickenham Stoop Stadium.

The hospitality facilities in the DHL and Charles Stanley Stands have also undergone renovations and redecorations.

[7] In November 2017, Harlequins unveiled plans to build a new state-of-the-art 25,000-seat stadium on the same Twickenham site.

[8] Concrete plans have not yet been released, and consultation with the local community and Richmond Council is currently ongoing.

On 24 October 2009 the ground hosted the second match of the 2009 Rugby League Four Nations between world champions New Zealand and defending tournament champions (in Tri-Nations mode), Australia which resulted in a 20-all draw, 12,360 people attended the game making it the largest rugby league crowd at the venue beating the 1997 World Club Championship match between the London Broncos and Canberra Raiders where 7,819 people attended.

In 2015, it began hosting what was intended to be an annual event in the World Rugby Women's Sevens Series.