Judith Gillespie quit her post last weekend after steering the SPTC to the forefront of educational debate during her five years in office and becoming something of a national celebrity. Mrs Kirby acknowledges she is not from the same mould.
"My background is not at all political and I have never been involved in a political party. I did not anticipate being landed with this job," says the Haddington housewife who describes herself as "an old-fashioned mother". She worked in computing before raising two sons and joining the school board at Kings Meadow primary.
That led to further involvement on the parent-teacher association and school board at Knox Academy in East Lothian. As chairman of the board at Kings Meadow she had the misfortune to cope with the aftermath of a blaze that destroyed the school's classrooms. Public meetings and consultations with officials and architects submerged her in the nitty-gritty of planning.
Her entrance into education politics coincided with the national campaign against primary testing. Seeing class work at first hand convinced her schools were already on the right lines, producing a lot of good work. "I am a supporter of teachers," she confesses.
Mrs Kirby has been on the SPTC's executive for three years and appreciates its role as a focus for parent concerns. She takes over a financially sound organisation - its insurance scheme for PTAs still pulls in the numbers - which is respected for its views.
Mrs Kirby does not envisage major changes, although she will not be based in the Edinburgh office as much as her predecessor. "I think the committee will be expected to do more and I hope to delegate," she says.
Besides her SPTC role, she will continue with occasional forays into schools as a lay member of the Inspectorate. She has already visited five primaries. When she is not looking after the family, inspecting schools or convening meetings, Mrs Kirby finds a release in the chorus of the Scottish Chamber Orchestra. She is well equipped to sing a new song at the SPTC.