This slight, articulate figure argued for the subject dearest to her heart, mustering all the charm and statistics she could, and blowing them away with her commitment and passion. “She was in some discomfort,” remembers Peter Coles, the county’s chief education officer. “But she was enormously cheerful and determined to overcome it.”

That drive and determination sums up Gillian Pugh, 52, who is leaving the National Children’s Bureau after 22 years to become chief executive of the Thomas Coram Foundation, the oldest children’s charity in the UK. She will be missed by the bureau, in particular, and by the the early years world, in general, for her work in putting her subject on the map.

“What she’s done that has been valuable is that she’s heightened not just the profile but people’s perception of the quality of the early childhood field, ” says Vicky Hurst, lecturer in early childhood education at Goldsmiths College, London. “She’s been a tremendous galvaniser in terms of putting the argument across,” adds Chris Trinnick, Lancashire’s chief education officer.

Dr Pugh, who has not yet been replaced by the NCB, combines intellectual ability with gritty practical concern for what happens to children and their parents. She is on a mission. Universally admired for her formidable networking skills, Dr Pugh has used her position as director of the NCB’s early childhood unit to hone her knowledge of her subject. She has used her administrative competence as a base for making things happen on the ground locally and with ministers and civil servants nationally.

As chair of the Early Childhood Education Forum, a disparate grouping of the warring tribes within early years education, she has done what no-one else could: get the tribes to pow wow.

It is surprising to the uninitiated to find such trouble in the early years field. One might expect the practitioners to sink whatever differences they have in the interests of the children in their care, but that has not always been the case.

Those who look after the under- fives in nurseries run by the health or social services have been suspicious sometimes of those who care for under-fives in the education service and vice versa. Maintained nurseries have resented private ones; the voluntary sector has sometimes felt shunned by the state; and so on.

Dr Pugh got them round a table. “She has embraced the fact that the private sector is here to stay,” according to Susan Hay, managing director of Nurseryworks Ltd, which runs five private London nurseries. “She has understood the importance of including rather than excluding the private sector when talking to others about policy.”

This pragmatism - her ability to work with politicians and practitioners of all persuasions - has earned her such epithets as “middle class” and “middle of the road”. Dr Pugh has her critics on the left as well as the right.

Her willingness to work the system does not endear her to radicals impatient for change - or to a few venerable male educationists who find her strength of mind and character hard to take.

But her accomplishments stand for themselves. In Hampshire, which was a poor provider of early childhood education, she helped to start a little revolution. After exhorting education and social services to work better together at her conference speech, she went on to advise the authority. Hampshire now has better staffed and funded reception years as well as centres of excellence in each area. Children start school in the September of the year in which they are five.

Her unit has worked with more than 90 other local authorities. In Shropshire more than 40 forums have been established between education and social services. “She understands both the education side and the local politics well,” according to Carol Adams, the county’s chief education officer. “She knows how things work and what can be done. Some people might have seen a good scheme here and there. She synthesises what she sees into a general framework. ”

At the National Children’s Bureau her involvement with local authorities so impressed the director John Rae Price that it was adopted as a modus operandi right across the NCB. “The skills she honed have now been replicated,” he says. “We’re working like this in child protection, residential care and children’s rights. The approach which Gillian developed in early years now characterises 70 to 80 per cent of the bureau’s work.”

At national level, Dr Pugh is used to eyeballing ministers and civil servants, giving them a piece of her formidable mind without climbing onto a soapbox. While the nursery voucher legislation was going through, for example, she stood her ground in opposition. “At every point that ministers announced changes to the voucher scheme, they called her in for a pre-briefing session prior to the announcement, aware that she would oppose but knowing that her reasoned response was one that they had to contend with,” says Mr Rae Price.

But for some observers it is her early work, putting the parents’ point of view in education for the under fives, for which she will be best remembered. Margy Whalley, director of research and development at the Pen Green Centre for Under Fives and their Families in Corby, says she will never forget Dr Pugh’s championing of the parents’ position in the early 1980s when it was not trendy. “Those early conferences were an inspiration,” she says. “The impact of what she has achieved has touched us all.”

In recent years she has been hitting the international scene, representing England on overseas trips. So, some people are perplexed by her move to the Thomas Coram Foundation, a London charity which has been languishing rudderless for a year and has been in difficulties.

They are incredulous that she’s leaving the NCB when everything she holds most dear may be about to be realised. “I’m leaving because many of the things I have been working towards are beginning to happen and I would like to do something that is related but different and challenging,” she says.

Dr Pugh may be moving to a local charity, but it is a venerable one with potential. It will be a bigger management job for her - 60 staff instead of 16 - and a challenge. “I will be needing all the skills I have developed here and needing quite a few more I should think,” she says.

She will also be her own boss. “Wherever she goes, she’s not going to settle for low horizons,” says Wendy Scott, chair of the British Association for Early Childhood Education.

A site next to Coram Fields is ripe for development and she hopes to redevelop that campus into a centre for children and families with a Pounds 1.3 million regeneration bid. She is also thinking about setting up some innovatory projects in the tradition of the late Professor Jack Tizard, a former director of the Thomas Coram Research Unit.

No-one has any doubt she will bring the foundation into the 1990s. “I am sure she will be able to cope as well as have an eye to the longer term,” says Roy Jobson, Manchester’s chief education officer.