Charter 88 was formed by progressive (mainly liberal and social democratic) British intellectuals and activists in 1988. Its name was inspired by that of Charter 77.
It quickly became a cross-party pressure group whose "signatories" were in effect members. It campaigned for freedom of information and for constitutional reforms including a written constitution (with a bill of rights that would be enforceable by the judiciary), and proportional representation, devolution of power to new elected bodies in Scotland and Wales.
The campaign printed advertisements in national newspapers calling on citizens to sign the Charter.
The party most sympathetic to the Charter's demands was the Liberal Democrats, but the Labour Party gradually adopted a substantial part of the programme as well.
In 1999, a group called Charter 99 was formed with the intention of promoting reform of the United Nations and other international bodies, but never really got off the ground.
Charter 88 still formally exists but is less active than formerly and is struggling financially.
Charter88 warned the government on Monday that it "makes little sense" to proceed with reform of the upper house without considering parliament as a whole, its relationship with the executive, devolution and changes to the legal system.
Charter88 says there is no need for any radical changes to the powers of the upper house, with the retention of its one year delaying power over primary legislation and power of veto over secondary legislation.
And Charter88 repeats the view, shared by many Labour backbenchers, that the government is failing to overhaul the "unacceptable" system of patronage to the upper house.
Those who signed the charter, including many figures from the arts, objected to what they saw as the autocratic leadership of Margaret Thatcher as prime minister.
They were consciously influenced by Charter 77, the human rights manifesto signed in communist Czechoslovakia by dissidents (including Václav Havel) in response to the 1975 Helsinki Agreements.
Charter88 was launched in a letter to New Statesman by 348, mostly Labour and Liberal Democrat party-leaning intellectuals.