In late 2022 or 2023, the 8th billionth person will be born on Earth. Yet as history has shown, the thinning of valuable resources necessary for sustaining not only life, but a good life, continues to drive wars, disease, and poverty. How can we use the 8 billion people we have on the planet today to shape the world we want tomorrow? In her provocative and penetrating new book 8 BILLION AND COUNTING, political demographer Dr. Jennifer Sciubba mines a long academic career, including a stint as a Department of Defense demographer, to show how a deeper understanding of fertility, mortality, and migration trends point us toward the investments we need to make today to shape the future we want tomorrow. The challenges that besiege our interdependent, interconnected world easily touch us all: disease, climate change, economic crisis—but so do the good fortunes for all 8 billion of us. In this interview, I speak to Dr. Jennifer Sciubba about how demographic trends (age, structure and ethnic composition) can signal crucial signposts for future violence and peace, repression and democracy, poverty and prosperity.