The world is urbanizing fast -- more than half the globe's people now live in cities. That fact makes the

management of urban areas a critical challenge and mayors more important than ever. Few mayors are attracting as much attention as Newark's Cory Booker, leading a city with a 40-year reputation for blight, crime, and poverty. Already well known, Booker became far more famous in late September when he and Facebook co-founder Mark Zuckerberg appeared on Oprah Winfrey's TV show to announce Zuckerberg's $100 million pledge to Newark schools. Booker, 41, was reelected in May by a comfortable margin, having replaced a notoriously corrupt administration in 2006. He went to Stanford on a football scholarship, then studied history at Oxford as

a Rhodes scholar and got a law degree at Yale. As mayor, he has reduced violent crime, his top priority; March was the city's first murder-free month in 44 years. Booker today has over a million followers on Twitter -- fewer than Lady Gaga but more than the Dalai Lama. He talked recently with Fortune's Geoff Colvin about teachers unions, rebranding Newark, and much else. Edited excerpts:

You first met Mark Zuckerberg in July. Eleven weeks later you two guys are on Oprah announcing that he's pledging $100 million for Newark schools. How did you do it?

I don't think it was me. The two of us were coming to the same conclusion at the same time, and we met at theright time. He had been thinking about making a major move in philanthropy for more than a year and wanted to get out there quick on the issue that's most important to him, which is education. We had concluded that if we were going to drive the level and scale of reforms that we envisioned, we were going to need some kind of attention-grabbing measure, as well as a shot of resources into the right places. We felt it could make dramatic change. So it was two men with the same idea meeting up.

Now you're going to have a lot of money for use in the Newark schools, but Newark already spends more money per student than most school systems in America, with worse results. How will you redesign the system to make this money effective?

That's a really important point to highlight in bold with a couple of exclamation points. Money in America has never been in line with performance -- our national spending on education is going up, but our performance has been stagnant. What's needed is not pouring new wine into old skins; it's to change the package altogether. We, the donor and I, have some very firm ideas. We recognize that in America we've all receded from our involvement in education. There is not the kind of engagement around educational issues that we want. We think we should pack our kids' lunch, send them off, and they should be returned to us scholars. That's just not the case anymore. We've created this convenient game of pass the buck, where parents are right to complain about the schools, the principals are right, maybe, to say they can't fire bad teachers, and teachers are right to say our kids are often showing up nutritionally and materially unfit to learn. The more we're able to say, "It's not my fault," the more we keep this descending cycle of mediocrity at best, and that's what we're trying to break with our resources.

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