GIVEN THE CALLS for the elimination of the informal international personnel system that awards the presidency of the World Bank to an American, President Obama was under some pressure in selecting a replacement for Robert Zoellick, the capable executive who is retiring in June. The president needed to find a nominee known not so much for political connections in Washington as for a demonstrated ability to carry on the bank’s mission of fostering development, especially in the poorest countries. We believe Mr. Obama has done just that in choosing Jim Yong Kim, a physician who has dedicated most of his career to delivering health care to destitute people worldwide.

Dr. Kim, who has been president of Dartmouth College since 2009, is a departure from the World Bank’s previous presidents in more ways than one. He is the first person of Asian descent to be nominated; Dr. Kim was born in South Korea and immigrated to the United States at the age of 5. Previous presidents have been bankers, politicians or, like Mr. Zoellick, technocrats who have previously served in government. Dr. Kim is the first nominee who has dedicated himself to development work, both in academia and in practice.

With fellow physician and Harvard professor Paul Farmer, Dr. Kim founded Partners in Health, an organization created to deliver quality health care to some of the world’s poorest people, including in Haiti, Peru and Rwanda. One of its innovations was to enlist the poor themselves in the delivery of their own health care. Later, at the World Health Organization, Dr. Kim oversaw an expansion of the delivery of anti-retroviral drugs to combat HIV to 3 million more people in the developing world.

Under Mr. Zoellick, the World Bank has demonstrated that it still has a role to play in a world where some developing countries attract abundant private capital. It remains a vital resource for the poorest nations; Mr. Zoellick saw through a capital increase that allowed the bank to help some of those countries through the global recession. As Columbia University economist Jeffrey Sachs, a candidate for the World Bank position, pointed out, “at its best, the bank serves as a powerhouse of ideas and a meeting ground for key actors who together can solve daunting problems of poverty, hunger, disease and environmental degradation.” Mr. Sachs withdrew his candidacy on Friday, strongly endorsing Dr. Kim.

The U.S. nominee may still face challengers from other nations; three African governments are backing Nigeria’s finance minister, Ngozi Okonjo-Iweala. But those who would reject an American nominee ought to consider whether the United States should be entirely excluded from leadership roles in international organizations. As it is, Americans are ruled out in competitions for the head of the International Monetary Fund and secretary general of the United Nations. While it would be well if the top jobs at international organizations were treated as open to all candidates, it’s also important that highly qualified nominees not be ruled out — even if they happen to be American.