The Peerage Act 1963 allows the holder of a British peerage to renounce his/her title for life within twelve months of the Act becoming law or of inheriting the peerage - or within one month of inheriting if a Member of the House of Commons. The peerage itself thus becomes dormant during the lifetime of the person but is afterwards inherited as if it had not been renounced.
The Act resulted largely from the protests of one man, Labour politician Tony Benn, who had been disqualified as an MP on inheriting the title of Viscount Stansgate. He and his political opponents, Sir Alec Douglas-Home and Quintin Hogg, were among the first to take advantage of it.
Since the abolition of the general right of hereditary peers to sit in the House of Lords, it is no longer necessary for hereditary peers to renounce their peerages in order to sit in the House of Commons. In 2001 John Thurso became the first hereditary peer to be elected to the Commons.
The Act also established the right of hereditary peeresses and of all Scottish peers to sit in the House of Lords.