 Adolescence is a period of risk and vulnerabilities. It's a time of emotional and social struggle, increased risks of accidents, suicide, homicide, aggression, violence, health problems related to risky sexual behavior, depression, alcohol, substance use, and yet it's equally a developmental period of great opportunities. It's a time of rapid learning, of exploration, of developing heartfelt goals, values and priorities, having inspired motivations that shape what you want and desire. And when we really put those together, it's a time when young lives can pivot rapidly in negative and positive directions. It's an inflection point in the trajectory. Globally, we are now facing the largest generation of adolescents in human history. 1.5 billion young people are coming of age with 75 to 80 percent of them in developing countries. Among nine to 13 year olds, a third are growing up in extreme poverty. In addition, we are also facing a historically unprecedented revolution globally in technology and social information processing. Young people are coming of age with this combination of new technologies that are often the early adopters of technology in ways that can amplify both the risks, the radicalization, the exploitation and the opportunities, the information, the education. Take those factors together and we have a precarious moment in human history. These multitude of young people coming of age, facing staggering challenges and amazing opportunities. It matters. The stakes are enormous. These young people are our future. And what can we do to tip the balance? Well, in early brain development, we've had tremendous progress from understanding this is a period of plasticity. We need to invest in getting young people off to a good start. And the global policies informed by that science have had a huge positive impact in the world. And plasticity doesn't end at age three or five. The onset of adolescence is another window of rapid growth, formational learning and developmental changes in the brain that are important. We need to understand that it creates a second window of opportunity for positive impact. At the Center on the Developing Adolescent in UC Berkeley, we're trying to bring the developmental science and policy together. The development of the human brain is this immensely complex self-organized learning system. And it's built around these interconnected nerve cells called neurons. This four-week-old fetus, this curved tube the size of a poppy seed is generating 250,000 neurons every minute, resulting in 100 billion neurons in a newborn. And then across infancy and adolescence, learning and brain development are inextricably intertwined. Learning and experience is driving brain development, which is driving social experience. And then the transition from childhood into adolescence starts with puberty. Puberty changes the bodies. It also changes the brains, especially emotional and social aspects of the brain. It creates charged emotions and sensitivity to social evaluation. Caring about being admired, liked, respected, accepted, it magnifies the emotions of both the positive side of that and the negative side. And in addition, the capacity to fall in love intensely emerges in adolescence. These high-intensity emotions are shaping deep social emotional learning experiences that influence identity and figuring out who we are. In adolescence, we search on our journeys for self-to-be, for other selves to love and work to do. In adolescence, we are discovering through trial and error, successes and failures, who we are in an adult context. And the particular experiences we have are shaping our identity over this period of time. Take, for example, social learning about admiration. If you're hungry to be accepted and liked and admired, and you're growing up in a culture where earning prestige is about showing kindness and compassion, and that's what you're practicing, that's going to shape social learning differently than if you're growing up in an impoverished area with a lot of violence. And then add in the internet of things where you can find infinite amounts of positive negative social learning experiences. Taken together, this makes a compelling case for investing in adolescence, scaffolding the positive learning experiences, having healthy versions of experiences around how admiration and prestige are shaped and getting purpose and value in our lives. We're at a tipping point. We're at a point where thinking about sustainable human development on this planet is approaching critical divide. And young people are critical part of the challenge and a crucial part of the solution. What could be more important than investing in tipping that balance in a positive way? Not only for the billion adolescents, but perhaps for the trajectory of human development on this planet. Thank you.