He married Christine Pamela Chapman in 1973 and the marriage ended in divorce in 1982. Around that time he became involved with Kate Allen (Amnesty International UK), now director of Amnesty International in the UK, but the couple separated in November 2001.
Livingstone and his current partner Emma Beal, also his office manager, have a son, Thomas, born 14 December 2002 at the University College Hospital, London, and a daughter, Mia, born on 20 March 2004 at the Royal Free Hospital in Hampstead. He also has three other children from previous relationships, whose existence was only publicly revealed during the London mayoral election in 2008. Livingstone is a noted "bon vivant", having twice worked as a food critic for London's "Evening Standard" newspaper and various magazines.
He is known for his enthusiasm for keeping and breeding newts.
Livingstone again stood for Parliament in the 1987 general election, winning a seat in the north-west London constituency of Brent East. He replaced Labour MP Reg Freeson who was a committed left-winger, but his relatively moderate ("sensible left") views made him vulnerable to the hard left in the early 1980s. Freeson was able to retain his seat at the 1983 general election, but was deselected in 1985 after a bitter struggle, described as "political 'murder'" in his Guardian obituary, and replaced as Labour candidate in Brent East by Livingstone.
In his maiden speech to Parliament in July 1987, Livingstone used Parliamentary privilege to raise a number of allegations made by Fred Holroyd, a former MI6 operative in Northern Ireland. Despite the convention of maiden speeches being non-controversial, Livingstone alleged that Holroyd had been mistreated when he tried to expose MI5 collusion with loyalist paramilitaries in the 1970s and the part Captain Robert Nairac is alleged to have played. He also voiced Colin Wallace's allegations of MI5 dirty tricks levelled at Harold Wilson, part of what became known as the "Wilson plot".
As a Labour backbencher, Livingstone lost the public platform he possessed as head of the GLC; furthermore, his brand of radical socialism was increasingly out of step with the Labour leadership, which had moved sharply towards the centre under the leadership of Neil Kinnock who now blamed left-wingers like Livingstone for Labour's 'unelectability.' Over the long term, though, it was Livingstone rather than Kinnock who was to achieve electoral success. In September 1987 he was elected to the party's National Executive Committee, although he lost this position two years later; he regained it in 1997 beating Peter Mandelson in what some interpreted as a rebuke to Tony Blair. He was re-elected MP in the general election of 1992, with a 6% swing to Labour in his Brent East constituency. Besides serving in the Commons, Livingstone held a number of other 'odd jobs' during this period, including game show contestant and host, after-dinner speaker, and restaurant reviewer for the "Evening Standard". In 1987 he published an autobiography-cum-political tract, "If Voting Changed Anything They'd Abolish It".
As a politician comfortable in light-hearted and satirical situations, in 1990, Livingstone made the first of seven appearances on the topical panel show "Have I Got News For You". For a long time, his first six appearances would stand as the show's record; his current tally of seven - the last being in 2002 - fall one short of the record for guest appearances currently held by Germaine Greer and Will Self.
In 1995, Livingstone appeared on the track "Ernold Same" by the band Blur, taken from the album "The Great Escape". Livingstone provided spoken word vocals and was listed as 'The Right On Ken Livingstone.'
Livingstone appeared in one of a series of advertisements extolling the virtues of cheese in the 1980s, appropriately endorsing red Leicester. On the other side of politics, Edward Heath advertised Danish Blue. Their respective choices are down to the colour red being associated with the Labour Party, and blue with the Conservative Party.
Livingstone was again re-elected in the 1997 general election, in which Labour was returned to power under the leadership of Tony Blair. Among Labour's proposals was the establishment of a Greater London Authority which was to be a strategic body: unlike the GLC the Greater London Authority would not provide any services to Londoners directly. The new Greater London Authority would be headed by a directly-elected mayor, who would be watched over by a 25-member Assembly.
Despite having earlier criticised the specific proposals for a new London-wide authority, Livingstone was widely tipped for the new post of Mayor. The mayoral election was scheduled for 2000, and in 1999, Labour began the long and trying process of selecting its candidate. Despite Blair's personal antipathy, Livingstone was included on Labour's shortlist in November 1999, having pledged that he would not run as an independent if he failed to secure the party's nomination. William Hague, then Leader of the Opposition taunted Blair at Prime Minister's Question Time: "Why not split the job in two, with Frank Dobson as your day mayor and Ken Livingstone as your nightmare?"
Labour chose its official candidate on 20 February 2000. Although Livingstone received a healthy majority of the total votes, he nevertheless lost the nomination to former Secretary of State for Health Frank Dobson, under a controversial system in which votes from sitting Labour MPs and MEPs were weighted more heavily than votes from rank-and-file members. On 6 March, Livingstone announced that he would run against Dobson as an independent, confirming speculation that he would renege on his earlier pledge. He was suspended from the Labour Party the same day and expelled on 4 April. Tony Blair said that Livingstone as mayor would be a "disaster" for London; he later said he was wrong in that prediction.
The result of the election – held on 4 May – was a foregone conclusion: Dobson, who it was alleged, had been pressured into running by the party leadership, unsuccessfully based his campaign on claims that Livingstone was an egomaniac, and the Conservatives remained becalmed after their catastrophic national defeat in 1997. Livingstone came out ahead in the first round of balloting with 38% of first-preference votes to Conservative Steven Norris's 27%; Dobson finished third, with 13% of all first-preference votes – just ahead of Liberal Democrat Susan Kramer, with 12%. Under the modified instant-runoff voting system employed for the election, only the votes cast for Livingstone and Norris were considered in the second round, where Livingstone won with 58% of first- and second-preference votes, versus 42% for Norris.
Livingstone continued to sit in parliament, as an independent having had the Labour whip withdrawn, until standing down at the 2001 General Election.