A conversation with the leaders of the Gates Foundation's Global Health Program: Gordon Perkin and William Foege.

Over the past 3 years, the Bill & Melinda Gates Foundation has committed more than $1.7 billion to help prevent and eradicate diseases that afflict people living in the world's poorest nations. The gifts have revitalized a number of major global health initiatives that in recent years had lost momentum and helped to refocus the world's attention on the health crises facing many developing nations.