The Socialist Alliance was a left-wing electoral alliance in England between 1992 and 2005.
The alliance grew out of local Socialist Alliances formed by the Socialist Party, Alliance for Workers' Liberty, Independent Labour Network and independent socialists from 1992 onward. They gradually coalesced into the national Network of Socialist Alliances. The Welsh Socialist Alliance was closely allied to the SA but had separate origins.
The Socialist Alliance was named and expanded in 1999 when other Trotskyist groups including the Socialist Workers Party, the International Socialist Group and Workers Power joined, as did the formerly separate London Socialist Alliance. In the 2002 local elections, the alliance gained one councillor in Preston, Lancashire. The Socialist Alliance had fraternal relations with the Scottish Socialist Party.
In late 2001, the Network of Socialist Alliances was transformed into a one-member-one-vote political party called the Socialist Alliance (a title already registered for electoral purposes).
The Socialist Alliance was riven by political disagreements. The Socialist Party left the Alliance in 2001 (after the conference that adopted one member one vote) while Workers Power left in 2003.
In 2003, the SWP, supported by the ISG, led the SA into an alliance with George Galloway and other figures involved in the Stop the War Coalition, to form the Respect Coalition. A minority of the SA objected to the way this decision was carried out and argued that the SWP were using their block vote to push their line. Many of these dissidents objected to Respect on principle and all objected to the way the decision to join it was carried out, many forming the Socialist Alliance Democracy Platform.