The Scotch of St. James

Floris (also J. Floris Ltd or Floris of London Holdings Ltd) is the oldest English retailer of fragrance and toiletries and is still family owned and run today by the 8th and 9th generations of the family.

Prestat Ltd is one of London's oldest chocolate shops. It has been awarded two Royal Warrants: from Her Majesty The Queen and Her Late Majesty Queen Elizabeth The Queen Mother.

Forbidden London (or Forbidden London Clubs) was a public relations company based at 91 Jermyn Street in the London district of St James's between 2008 and 2012 during which time it was owned by James Wilson and David West. The company promoted the nightlife sector, particularly by utilising the Internet to attract guests to events at leading nightclubs in Soho and Mayfair. Rivals at the time of the inception of Forbidden London included London Parties, operated by Nick House - future partner in Mahiki; and Met Parties. The company was notable for staging the first performance of Vivienne Westwood's Active Resistance to Propaganda manifesto at the Bloomsbury Ballroom on Friday 4 December 2009. The performance starred Vivienne Westwood and Michelle Ryan. As the company was based above the nightclub and Russian restaurant at 91 Jermyn Street, both owned by David West, the company was named in online conspiracy theories related to the poisoning of Alexander Litvinenko. This escalated following the unlawful killing of David West although the two incidents were found to be unconnected. In 2010 Forbidden London organised Raef Bjayou's 007 party for UK TV show Party Wars at Amika nightclub in High Street Kensington. Raef came second in the show. In 2011 Forbidden London was nominated for Best Entertainment by Spear's for their Design for Living Awards 2011.In August 2011 Forbidden London announced 1000 job opportunities for young people in London.On 23 October 2017, the 60th anniversary of the Hungarian Revolution of 1956, it was announced on the Forbidden London Facebook page that the brand would relaunch.

Paxton & Whitfield are one of the oldest cheesemongers in England. Their main shop is located at 93 Jermyn Street, London.

The Cavendish Hotel is a modern 4-star, 230-bedroom, luxury hotel in St James's, London, United Kingdom, facing the restaurant front of Fortnum and Mason on Piccadilly. Across Piccadilly is Mayfair. It is currently known as "The Cavendish London" and it is owned by CapitaLand. Its main entrance is on Jermyn Street, and a side entrance is on Duke Street, St James's. Jermyn Street is an established retail and urban leisure street which has bespoke gentlemen's clothing stores, shoe/bootmakers and barber shops. The hotel gained notoriety during the 1902–1952 management of the self-made hotelier and socialite Rosa Lewis, who was also known as the "Queen of Cooks" and "The Duchess of Jermyn Street"; damaged in the London Blitz, it was torn down in 1962. The present edition of the hotel was built on the site in 1966.

Jermyn Street is a one-way street in the St James's area of the City of Westminster in London, England. It is to the south of, parallel, and adjacent to Piccadilly. Jermyn Street is known as a street for gentlemen's-clothing retailers.

Tramp is a private, members-only nightclub located on Jermyn Street in central London, England. It was founded in 1969 by Johnny Gold, Bill Ofner and Oscar Lerman. The club built a reputation for discretion, banning photography and gossip writers from inside, and is popular with celebrities.

The Matthiesen Gallery is an art gallery in St James's, London, England, founded in 1978 by Patrick Matthiesen, son of Francis Matthiesen, an art dealer of Berlin and London. It operates as both a commercial gallery and an art museum. The gallery is located at 7-8 Mason Yard, Duke Street St James's. An earlier Matthiesen Gallery was operated by Francis, first in Berlin, then in London, after he fled Nazi Germany.

The High Commission of Cyprus is the diplomatic mission of Cyprus in the United Kingdom. It is located at 13 St James's Square, next door to the London Library and very close to Chatham House.In 2012 there was a small protest outside the High Commission by people claiming to have been mis-sold property on the island.

The Red Lion is a Grade II listed public house at 2 Duke of York Street, St James's, London, SW1.It is on the Campaign for Real Ale's National Inventory of Historic Pub Interiors. It was built in 1821.

Indica Gallery was a counterculture art gallery in Mason's Yard (off Duke Street), St James's, London from 1965 to 1967, in the basement of the Indica Bookshop. John Dunbar, Peter Asher, and Barry Miles owned it, and Paul McCartney supported it and hosted a show of Yoko Ono's work in November 1966, at which Ono met John Lennon.

Princes Arcade is an arcade of shops running between Piccadilly and Jermyn Street in central London. It is home to a number of small menswear shops and boutiques.The arcade is located on the site of the former Princes Hotel, designed by Edward Robert Robson for the Royal Institute of Painters in Water Colours and opened in April 1883. A westward extension of the hotel was built between 1911 and 1913, which is now Nos. 39-40 Jermyn Street. The arcade was constructed between 1929 and 1933, linking the two streets. The hotel was subsequently converted into offices.The arcade was refurbished by the Crown Estate in 2018 as "a space for innovative retail brands".