CAMPED-OUT halfway up a mountain, the bitter wind searing at her tent, and the sounds of braying beasts and men snoring filling her ears, Hermione Youngs must have wondered what on earth she was doing. Less than a decade ago, she had been a regular wife and mother-of-three, working as a medical manager and living in Guisborough, east Cleveland. Now she was engaged in one of the biggest challenges of her life - to supervise the safe passage of 200 tonnes of vital foodstuffs, medicine, and other aid across the Pakistani/Afghan border.

That night, as she lay freezing on the rough mountainside, 3,800m above sea level, doubts of succeeding in the task set in. The day had not been as productive as anticipated, with sheeting rain slowing the jeeps' progress from the village of Garam Chashma up to the 3,000m mark, where donkeys were waiting to carry the cargo through the Shah Saleem pass and into Afghanistan.

As a result, the team of aid workers, of whom the leader, Hermione, was the only woman, knew they faced another interminable night on the slopes. And with food supplies running low and the hint of snow in the air, time was of the essence.

Looking back from the comfort of the United Nation Children's Fund (Unicef) head office, in London - where she is briefly ensconced before jetting off for promotional work in Holland, Norway and Belgium - Hermione is conscious of the enormity of her challenge.

As an Afghan education officer for Unicef, she had supervised the same convoy, including a final, two-day passage by donkeys through the otherwise impassable Shah Saleem pass, three times before. But on those occasions, the cargo was a comparatively modest 80 tonnes of educational supplies. She was asked to take the extra 120 tonnes this time after the outbreak of war cut off the usual transport routes for delivering winter sustenance to the cold and starving.

"It was a logistical nightmare," she remembers. "But it was fairly obvious that, for the foreseeable future, we were not going to have access to other means of transport."

Looking at this 56-year-old woman, casually dressed in beige trousers, an embroidered tweed waistcoat and blue shirt, it is hard to imagine her swathed in the garb of Afghan women, roughing it in the small house in Badakhshan, northern Afghanistan, where she has lived for the past nine years. Her willingness to give up a good job and basic comforts like running water and electricity seems unfathomable. But even in appearance, certain quirks betray her eccentricity and mark her out as anything but a typical grandmother.

For a start, she is youthful in both looks and attitude, her nut-brown hair cut short and spiky and her eyes twinkling with the promise of mischief. She wears a very long, loud, and ethnic-looking scarf, and two strings of blue and white love beads dangle from her glasses.

She explains that her decision to embark on voluntary work coincided with a hiatus in her life. "My husband had died and the children were either at university or away from home. I didn't fancy staying in a nine-to-five job any longer, so I got a post with the VSO."

Starting immediately in Afghanistan, she worked for the Voluntary Service Overseas (VSO) for almost two years, before transferring to a non-governmental organisation and spending time at a hospital.

For the best part of six years, she worked for the Norwegian Afghanistan Committee as programme manager for Badakshan, supervising such projects as building a road and a school, providing earthquake relief, and supporting an orphanage.

She transferred to Unicef in 1998, when she was asked to take over a new education project. During her time in Afghanistan, she has used her management skills, powers of persuasion and stubbornness to win the co-operation of often intractable officials. She has also won people's respect - no mean feat for a woman in a Middle Eastern country.

On the latest trip, Afghan tribesmen were so impressed by her that they held a Buzkushi contest in her honour. The sight of men on horses charging after a stuffed goatskin may not be every woman's idea of a compliment, but Hermione understood it for what it was, a simple and genuine tribute.

During her time in Afghanistan, she has understandably built up great affection for its people. Some of her best friends are Afghans, and it was while in their company, in Islamabad, that she heard news of the war.

"It was obvious that there was going to be some form of retaliation after what happened in New York, but we all desperately hoped it wouldn't be this," she says. "I burst into tears when I heard."

Now exiled from her home, she hopes the United Nations will soon revoke its ban on non-nationals entering Afghanistan. "I would hope the UN would let the international staff return to work alongside the national staff. They need our support, both work-wise and morally."

While she has already done more than her fair share to help, with the convoy of aid she led as far as the border area now saving lives, she cannot wait to get back. Afghanistan is, after all, her home, and as she puts it, "children still need schooling". Above all, she wants to be there for her adopted countrymen at their time of greatest need.

Before the war, it was estimated that 300,000 Afghan children died every winter and this year, it is predicted that the figure could rise by 100,000 unless foreign aid is pumped in now. Last week, Hermione did her part to raise British awareness by helping launch Unicef's Afghanistan Crisis Leaf Appeal, alongside Pakistan cricketer's wife Jemima Khan.

When asked if, as a mother and grandmother, it hurts her especially to see children suffering, she replies unemotionally. "I think everyone I work with feels the same. Every child has the right to live."

But get her on to less sombre matters, and she betrays a heartfelt affection for Afghans that hints at real despair over their plight. Recounting the tale of her visit to a remote village, where a road had just been built, she laughingly recalls: "They had never seen a car before, and the children asked how I milked and fed it. The people are absolutely wonderful. They have a northern sense of humour, cracking jokes about other people."

While her current plan is to spend Christmas in New Zealand with her son Mark and two grandchildren, who she has not seen for two years, she will return to Pakistan first. If she is allowed to cross the border into Afghanistan, she coyly admits it will be tempting to stay. But for now, she must be content to watch and wait as the shadow of war engulfs her beloved country.