On the day after Tom Arnold was appointed the new chief executive of Concern Worldwide, two planes crashed into New York's World Trade Centre and changed our world forever. The week before he took up the post, the US started bombing Afghanistan.

The first event inevitably submerged the announcement of his appointment; the second has put Concern in or near the eye of the storm. Mr Arnold has had to hit the ground running, as the Republic's largest aid agency grapples with a disaster of massive and unfamiliar proportions.

In the past month, the agency has collected more than £2.5 million (€3.2 million) for

the humanitarian crisis in Afghanistan. The amount raised stands in stark contrast to the dribble of donations received before September 11th, when the media and politicians did not want to know about the problems of that country.

Mr Arnold does not enjoy the profile and level of media access of his predecessor, David Begg, who left in the autumn to become president of the Irish Congress of Trade Unions. Othe other hand, he is intimate with the organisation he now heads, having served on the council of Concern since the mid-1980s.

As chairman of the agency between 1995 and 1999, he helped to steer Concern through the difficult transition period that followed the departure of Fr Aengus Finucane as chief executive. The missionary zeal of Fr Finucane and the other Holy Ghost fathers who set up Concern in the wake of the Biafran crisis in the early 1970s was replaced by Mr Begg's emphasis on partnership and modern management techniques.

Back in 1997, Mr Arnold played a central role in picking Mr Begg, a trade unionist, over other candidates with greater experience in development. Now Concern has effectively opted for an insider in preference to someone from outside the organisation.

Its choice also represents a preference for a candidate from the public sector over private industry.

A number of leading figures in the business and voluntary sectors in Dublin failed even to make the final shortlist this summer as the agency opted to stick with the familiar.

Mr Arnold fits the description of "a technocrat" to a tee; an experienced economist, he is affable but unshowy, and he has a lengthy track record in the corridors of the Civil Service and the European Commission.

From Lusk in north County Dublin, he studied agricultural economics in UCD and has an MBA from the Catholic University of Louvain in Belgium.

The new chief executive joins Concern from the Department of Agriculture, where he was assistant secretary since 1993. In the aftermath of the beef tribunal, he fought hard and successfully to minimise the fines Brussels sought to impose arising from various activities in the industry. He was also responsible for the financial management of the Department's £2 billion annual budget.

Ironically, the trained agricultural economist had already spent a decade on the other side of the fence with the European Commission in Brussels. For most of this time he dealt with development issues, spending three years working as an agricultural adviser in the Ivory Cost and Malawi.

Mr Arnold acknowledges he is a "civil servant through and through". However, as he points out, he has a wide range of outside interests, most notably his involvement in pro-EU bodies such as the European Movement and the Institute of European Affairs.

Although Concern's business is charity, it is also a multinational, albeit of an unusual kind. How many other Irish companies can boast an annual turnover of £50 million, with operations in 26 countries? The agency has 80 staff in Dublin, 130 expatriates overseas and 2,500 local staff. Last year, it collected £14 million in donations from the public, and used this to leverage even greater sums from the Irish, British and US governments and the EU.

In recent years, Concern has led the way in introducing slick marketing techniques to persuade people to make donations. The agency uses a professional fund-raising company to gather contributions and has been particularly successful in persuading people to pay by direct debit.

The overheads are high but you cannot argue with the results; today, more than 100,000 people are Concern donors.

As a consequence, the agency is "in good shape," according to Mr Arnold, who says he will not be proposing any major shift in direction.

A new strategic plan to be adopted shortly proposes a greater emphasis on specific areas of work - primary healthcare, primary education, AIDS, initiatives to secure people's livelihoods and emergencies.

Arnold also sees investment in women as a crucial ingredient to success in development.

"There is a huge amount of evidence to show that if you invest in women and their education, the effects are huge. You see it in the way households are managed and in reductions in child deaths and birth rates."

Fifty years after the aid business started, it has precious few successes to show for the billions of pounds pumped into poor economies. However, Mr Arnold says "it isn't all bad news". He points to Concern's successes in providing education for thousands of Bangladeshis, or the achievement of its child-tracing scheme for survivors of the Rwandan genocide. "If you come back in a year's time, I'm sure there'll be many more."

He concedes, however, that "a lot of other factors have prevented aid from being as effective as it could be".

War and other kinds of conflict are the most obvious impediments. In these circumstances, aid can sometimes serve as nothing more than "a sticking plaster".

If there is a major lesson from September 11th, Arnold believes it is "the dawning realisation that a world with huge levels of inequality is a dangerous world". The duty of the international community is "to provide a sense of hope for the future".

The way to achieve this is to improve the terms of trade for poor countries, to help provide better government and to find ways of resolving conflicts.

In the war in Afghanistan, Concern has taken an overtly political stance, arguing for the creation of humanitarian corridors to allow aid to get into the country safely. Yet Mr Arnold, speaking personally, says he is "broadly comfortable" with the US-led war because it is operating according to the "broad international consensus" expressed by the UN Security Council.