It speaks volumes about the public perception of trade unions that fewer people can name the leader of the country's biggest public sector union than can tell you who runs the railwaymen.
The name that so easily slips the memory is Dave Prentis, general secretary of Unison, who is still below most people's radars after more than 10 years as one of the most powerful figures in the trade union movement, and even as the country braces for the biggest public sector strike since the strife-torn 1970s.
It is not that Unison has been quiescent under Prentis's long stewardship. It has been involved in any number of local disputes, such as the strike by hundreds of council staff in Southampton in July, protesting against cuts, or the Leeds refuse collectors' strike in 2009. In 2007, Unison balloted its members for a nationwide strike over pay, but the majority in favour was too narrow and the action did not go ahead. The following year, hundreds of thousands of its members working for local authorities went on strike for better pay.
Yet none of these actions has given the union or its long-serving leader the kind of notoriety than Bob Crow and the RMT have acquired by their sporadic disruptions of the London Underground. Crow leads a union with fewer than 80,000 members, which is not affiliated to Labour, while Unison, which Prentis has led for longer than Crow has been the RMT's general secretary, has nearly 1.4 million members and contributes about £1.5m a year to Labour Party funds.
Tony Blair once complained of "the scars on my back" from his battles with public employees, yet there is no mention in his memoirs of the man who led the biggest public sector union through most of his premiership.
The reason this quiet man has so little visibility is that he does not conform to the idea of what a big union boss should be. Union barons are supposed to be arrogant, opinionated, politically motivated and greedy. Prentis speaks softly, rarely expresses an opinion that is not strictly related to his job, and his slight physical stature is testimony to the fact that he eats sparingly.
In newspaper parlance, he is described as a member of the "awkward squad", alongside Crow, and Mark Serwotka of the Public and Commercial Services Union, or, more recently, Len McCluskey of Unite – union bosses who were not going to do the bidding of the Labour leadership. At least one right-wing commentator fulminating about next week's strike suggested that Prentis has deliberately engineered this dispute because he wants to pull his members out on strike in the hope of bringing down the Government, just as Arthur Scargill once hoped to use the miners as the battering ram to break the Thatcher government.
But that is not how Prentis is seen by those who have actually dealt with him, either in government, or in the Labour Party, or even by others in the trade union movement. When he was elected general secretary of Unison in 2000, he was not the candidate of the far left, and when left-wing union activists in the union movement talk approvingly about the "awkward squad", they do not include Dave Prentis in this pantheon.
But Tony Blair, who had little regard for union leaders who made trouble for him, retained a sneaking respect and affection for Prentis. Ministers in the Coalition Government may have a similar attitude, but are unlikely to say so days ahead of a national strike.
"He always had a very positive relationship with No 10," Nita Clarke, the former Downing Street adviser who was Blair's link with the unions, said. "Dave was somebody of substance. He's extremely intelligent, and a very good leader of the union, very, very highly thought of throughout government. Tony Blair had a great deal of respect for him."
The two hit it off partly because they were of the same generation – Prentis, who is now 61, being older by three years. His two daughters by his long-term partner Liz Snape, Unison's head of policy, are roughly the same age as Blair's children, the elder girl being now out of her teens. Prentis was one of the first big union leaders to acknowledge that the spectacle of union bosses stomping around Labour conference wielding their block votes was bad for Labour and bad for the unions.
When Ed Miliband beat his brother in last year's Labour leadership contest, Charlie Whelan could not resist spreading the word among journalists that the Unite union's backing had been vital for the younger Miliband. The figures show that Unison's endorsement was decisive too, but Prentis's people did not think it wise to brag about it.
There was another, more personal reason for Blair's solicitude towards the occasionally awkward public sector union leader – relief that he was alive. In 2000, just before he took over the general secretaryship from his predecessor, Rodney Bickerstaffe, Prentis went to the doctor complaining of indigestion – and was diagnosed with cancer of the oesophagus.
After chemotherapy, he had his food pipe and part of his stomach cut out – and as if that were not enough, he contracted MRSA while he was in hospital. He could no longer indulge himself with heavy meals and strong drink in the grand and greedy manner associated with certain other union bosses, even if he wanted to.
What pleases ministers but exasperates the left about Prentis is that if he has an ideological worldview, he keeps it hidden behind the self-effacing exterior of a professional negotiator. His politics are to the left of the Labour leadership, but the views of the people he represents, all of whom work for the public sector, and most of whom are low paid, are to the left of the rest of the general public's.
Prentis is not by any measure badly paid. According to Unison's most recent annual accounts, his total salary and benefits in 2010 came to just over £101,000, plus £32,818 paid into his pension pot. But his early memories are of being the clever boy from a Catholic family living in the poor quarter of Leeds who had passed his 11-plus and joined the kids from better-off families at Leeds Grammar School. Since university, his entire working life has been immersed in the union movement, with no apparent ambition to go into politics, unlike so many other trade union officials.
"Dave's a negotiator. He wants to negotiate a deal. He'll stay and negotiate for as long as it takes," a Unison official said yesterday.
Employment law makes it much harder than it was in the 1970s for a union leader to call its members out on strike, but also, paradoxically, it makes a strike harder to call off. Once a strike ballot has been called, the union has 28 days to act or the ballot is invalid.
Prentis the negotiator may have hoped that 28-day window would concentrate ministers' minds enough to squeeze a firm offer out of them that would allow him to claim a success without a strike. That has not happened, and hundreds of thousands of low-paid, predominantly female members of Unison will sacrifice a day's pay and risk alienating public support next week. There is a limit to how often they can be persuaded to do it again.
When the strike is over, the Unison's semi-visible elder statesman will be hoping he can go back to doing what he does best – negotiating and negotiating until the other side has been worn down.
A life in brief
Born: David Prentis, 1950, Leeds.
Family: His partner of 24 years is Liz Snape, Unison's director of policy; they have two daughters.
Education: Leeds Grammar School; BA in history at University of London; MA in industrial relations at University of Warwick.
Career: He joined the union Nalgo (now dissolved) in 1975, and was appointed Unison's deputy general secretary in 1993, becoming general secretary in 2001.
He says: "Class still divides. Geography still divides. Working people, our people, are taking the hit. It's immoral and it's got to change."
They say: "Dave was somebody of substance. He's extremely intelligent, and a very good leader of the union." Nita Clarke, former Downing Street adviser