Equestrian statue of William III, London

St James's Square is the only square in the St James's district of the City of Westminster and is a garden square. It has predominantly Georgian and Neo-Georgian architecture. For its first two hundred or so years it was one of the three or four most fashionable residential streets in London. It now has headquarters of a number of well-known businesses, including BP and Rio Tinto Group; four private members' clubs, the East India Club, the Naval and Military Club, the Canning Club, and the Army and Navy Club; the High Commission of Cyprus; the London Library; and global think tank and peace-promoter Chatham House. A main feature is a high, stone-plinthed equestrian statue of William III erected in 1808.

The murder of Yvonne Fletcher, a Metropolitan Police officer, occurred on 17 April 1984, when she was fatally wounded by a shot fired from the Libyan embassy on St James's Square, London, by an unknown gunman. Fletcher had been deployed to monitor a demonstration against the Libyan leader Muammar Gaddafi, and died shortly afterwards. Her death resulted in an eleven-day siege of the embassy, at the end of which those inside were expelled from the country and the United Kingdom severed diplomatic relations with Libya. Between 1980 and 1984 Gaddafi had ordered the deaths of several exiled opponents of his regime; bombings and shootings, targeted at Libyan dissidents, occurred in Manchester and London. Five Libyans thought to be behind the attacks were deported from the UK. During the anti-Gaddafi protest on 17 April 1984, two gunmen opened fire from the first floor of the embassy with Sterling submachine guns. In addition to the murder of Fletcher, eleven Libyan demonstrators were wounded. The inquest into Fletcher's death reached a verdict that she was "killed by a bullet coming from one of two windows on the west side of the front on the first floor of the Libyan People's Bureau". Following the breaking of diplomatic relations, Libya arrested six British nationals, the last four of whom were released after nine months in captivity. Two years after Fletcher's murder, the event became a factor in the decision by the British prime minister, Margaret Thatcher, to allow the US bombing of Libya from bases in the UK. In 1999, a warming of diplomatic relations between Britain and Libya led to a statement from the Libyan government admitting culpability in Fletcher's shooting, and the payment of compensation. British police continued their investigation until 2017. Although sufficient evidence existed to prosecute one of the co-conspirators, no charges were brought as some of the evidence could not be raised in court due to national security concerns. As at 2022 no one has been convicted of Fletcher's murder, although in 2021 the High Court of Justice determined that Gaddafi's ally Saleh Ibrahim Mabrouk was jointly liable for Fletcher's murder.

The Junior Carlton Club was a London gentlemen's club, now dissolved, which was established in 1864 and was disbanded in 1977.

Chatham House, also known as the Royal Institute of International Affairs, is an independent policy institute headquartered in London. Its stated mission is to provide commentary on world events and offer solutions to global challenges. It is the originator of the Chatham House Rule.

5, St James's Square (anciently Wentworth House) is a Grade II* listed historic townhouse in London, England, built 1748–51 by William Wentworth, 2nd Earl of Strafford (1722–1791) to the design of Matthew Brettingham the Elder. It remained the London residence of the descendants of his sister until after 1968, and in 1984 was the site of the "Libyan Peoples' Bureau" from which shots were fired which caused the murder of Yvonne Fletcher.

The Canning Club is a gentlemen's club based in London, formerly named the Argentine Club, founded in 1911, and is for those with a particular link to, or special interest in, Argentina and other Latin American countries. As the previous name suggested, it was originally established as a club for nationals of Argentina, and much of its income was derived from Argentine-based British businesses. When these businesses were nationalised by Juan Domingo Perón from the 1940s, the club was deprived of its main source of revenue. Adapting to the situation, it redefined its remit more broadly to Latin America in general, and in 1948 was renamed as the Canning Club, in honour of George Canning, who had strong links to Latin America. The club was based in Hamilton Place, Mayfair, until 1970, when it began sharing the premises of the Naval and Military Club, first at Cambridge House, 94 Piccadilly, and from 1999 at 4 St. James's Square.

The Naval and Military Club, known informally as The In & Out, is a private members club located in St James's Square, London. It was founded in 1862 for gentlemen of the British Armed Forces. It now also accepts female members, and members who have not served in the armed forces, but continues to observe service traditions.

The Army and Navy Club in London is a private members club founded in 1837, also known informally as The Rag.

The Portland Club is a London card-playing game club and the recognised early authority on the games of whist and bridge. It is reputedly the oldest card club in the world. Founded in October 1814 as the Stratford Club, 1, Stratford Place.Following the bankruptcy of its bank, Marsh, Sibbald, and Co., in October 1824, the club had to change its partnership and was renamed the Portland Club in January 1825. Two newspapers reported the event: The Star of 5 November 1824 advertised: “In consequence of the failure of the Berners-street Banking-house, which possessed its funds, the Stratford Club, in Oxford-street, is about to be dissolved.” And, on 7 January 1825, The Morning Herald wrote: “It is the rump of the Old Stratford Club, we now hear, which assumes the imposing title of the Portland; and not, as we had been led to suppose, an entirely new Society.” The Portland Club remained in its Stratford Place/Oxford Street premises until 1890. It then moved to 9, St James's Square, in a house that the club had bought there. However, in 1943 the Royal Institute of International Affairs bought the house from the Portland Club, which moved to Charles Street, an address which it left in 1969 for 42, Half Moon Street. From 1999 to 2014, the Portland Club was housed in the Savile Club, 69 Brook Street, then moved to its present premises. The Club now meets in the Army and Navy Club at 36-39 Pall Mall, London SW1.

The East India Club is a gentlemen's club founded in 1849 and situated at 16, St James's Square in London. The full title of the club is the East India, Devonshire, Sports and Public Schools' Club due to mergers with other clubs. The club was originally founded for officers of the East India Company, and its first Patron was Prince Albert. On 21 June 1815, the Prince Regent (later George IV) was the principal guest at a dinner party held at 16 St James's Square, when he heard the news of the victory at Waterloo when Major Henry Percy, aide-de-camp to the Duke of Wellington, presented the Prince Regent with four captured French eagles and Wellington's victory despatch.

Den Norske Klub (The Norwegian Club) is a social club based in London. It was founded on 17 May 1887. Its members are Norwegians living in London or Britons with a connection to or interest in Norway. It is the oldest club of its kind in the UK and is still an important meeting place for the Norwegian community in London. As a result of DNK's long existence and extensive networks, DNK attracts high caliber speakers and guests to its events including royals, celebrities, business leaders, and members of parliament.

The Royal Automobile Club is a British private social and athletic club. It has two clubhouses: one in London at 89 Pall Mall, and the other in the countryside at Woodcote Park, near Epsom in Surrey. Both provide accommodation and a range of dining and sporting facilities. The Royal Automobile Club has some female members. It is best-known for establishing the roadside assistance service RAC Limited, though this is no longer owned by the club.