He subsequently helped to lead the SDP into the merger that formed the Liberal Democrats in 1988, and later served as the party's leader in the House of Lords between 1997 and 2001.

Within the Labour Party, he was known for being a highly effective organiser around centrist causes such as multilateral nuclear disarmament and Britain's membership of the European Economic Community.

With Labour drifting to the left, Rodgers joined Shirley Williams, Roy Jenkins and David Owen in forming the Social Democratic Party (SDP) in 1981.

He remained outside Parliament, unsuccessfully contesting Milton Keynes for the SDP in the 1987 general election, until he was created a life peer as Baron Rodgers of Quarry Bank, of Kentish Town in the London Borough of Camden, on 12 February 1992.

[12] Rodgers was a main character in Steve Waters's 2017 play Limehouse, which premiered at the Donmar Warehouse; he was portrayed by Paul Chahidi.