By 2015, it is projected that we will be sharing the planet with 7.3 billion people. While the human population swells -- especially in parts of the world where there is more poverty, disease, famine, and political instability -- we must continue finding innovative ways to achieve global health goals. Population health coheres infectious disease, NCD's, and nutrition with behavioral economics, climate change, agriculture, resource scarcity, and the entire living ecosystem. To improve health, from rural villages to booming metropolises, there is a need for transdisciplinary and collaborative global health action. This panel convenes experts from around the Bay Area to explore cutting-edge research tackling complex global health challenges, and to debate the priorities for a growing, interconnected, and crowded Earth.