How many people the planet can sustain is a question that has occupied scientists, economists, and policymakers for decades, yet no single answer exists.How many people the planet can sustain is a question that has occupied scientists, economists, and policymakers for decades, yet no single answer exists. This book examines the concept of Earth's carrying capacity through the lenses of agriculture, water resources, energy systems, and ecological limits, showing how estimates have shifted over time as technology and consumption patterns change. Generated with the assistance of artificial intelligence and reviewed for clarity and accuracy, the book offers you a structured introduction to the methods researchers use to model population limits, the assumptions behind competing projections, and the trade-offs between consumption, equity, and sustainability. You will learn why estimates range so widely, what factors most influence future scenarios, and how choices made today about resources and policy may shape outcomes for generations to come.How many people the planet can sustain is a question that has occupied scientists, economists, and policymakers for decades, yet no single answer exists. This book examines the concept of Earth's carrying capacity through the lenses of agriculture, water resources, energy systems, and ecological limits, showing how estimates have shifted over time as technology and consumption patterns change. Generated with the assistance of artificial intelligence and reviewed for clarity and accuracy, the book offers you a structured introduction to the methods researchers use to model population limits, the assumptions behind competing projections, and the trade-offs between consumption, equity, and sustainability. You will learn why estimates range so widely, what factors most influence future scenarios, and how choices made today about resources and policy may shape outcomes for generations to come.