For 25 years, she has been proactive in the interests of better opportunities for children and families. Her work, more than any other individual's, has led from the desert days of the Eighties and before, when early childhood was barely considered a political issue, to today's "every child matters" agenda. The Sure Start programme to provide education, care and other services for young children in poor areas and support for parents was launched at Coram Family's London campus in sheep-studded Coram Fields by the Prime Minister.
Dame Gillian, who became a dame in the New Year honours list, has networked, set up pressure groups, advised governments at home and abroad, and published more than 30 books.
"Gillian is the most influential under-fives thinker of this generation," says Naomi Eisenstadt, head of Sure Start.
As head of the National Children's Bureau's early childhood unit in the Eighties and Nineties, she was a determined figure, setting out her vision for the future in The TES: "Every child between birth and the age of six would have access to an early childhood centre. Each centre would form part of a network of services for families and be linked to a child health centre."
These centres, she wrote, would have facilities and access to learning for parents, and children would receive an active curriculum based on need.
Having seen Britain set on the path toward to this vision, with 3,500 children's centres planned by the Government, is she retiring to the countryside? Not exactly. "My main aim is to get my weekends back," she says.
So although leaving Thomas Coram after eight years building the charity into a major institution, she will still work with the National Family and Parenting Institute, with Sure Start, advising the Department for Education and Skills and serving as a consultant for local authorities.
She sees her greatest achievement as "probably being focused over 25 to 30 years on the needs of young children and how they learn, and keeping in the Government's eye what needs to be done". So much of what she has pushed for is now taken for granted: the central role of parents, the value of agencies working together and the confluence of education and care for children.
But of course she is never satisfied. Even when great strides are made, "nothing is ever quite good enough", says Naomi Eisenstadt.
Gillian Pugh's passion for working on behalf of young children arose out of an NCB project. "I started off working on raising the school-leaving age," she says, "but what became evident was the importance of the early years in brain and social development, and the differences we could make."