a foundation that evolved in response to those it committed to serve

Andy Posner wanted to bring microloans, a much-heralded form of aid in the developing world, to America's "underbanked" populations. When he established Capital Good Fund, it was with the notion that as in the developing world, the loans would be used to spur small-business growth.

What he discovered, though, was that the people he wanted to serve had a big need for plain old personal loans. If they wanted to put down security loans for an apartment or make a car repair, their only alternativ...