Santa Marta: Matt Lauer tours of one of Rio de Janeiro’s oldest favelas

Up to a quarter of Rio’s 7 million people live in favelas, hundreds of hillside communities that have become synonymous with poverty and crime. But as TODAY’s Matt Lauer visits one of the oldest, Santa Marta, with Theresa Williamson, who runs a nonprofit to help the favelas, he finds signs of hope amid daunting challenges surrounding education, health and sanitation. (Run time: 5:03)