This handbook presents up-to-date theoretical analyses of problems associated with the moral standing of future people in current decision-making. Future people pose an especially hard problem for our current decision-making, since their number and their identities are not fixed but depend on the choices the present generation makes. Do we make the world better by creating more people with good lives? What do we owe future generations in terms of justice? Such questions are not only philosophically difficult and important, but also directly relevant to many practical decisions and policy issues, including on climate, health, population control and taxation. If we are to adequately assess such issues, we must be able to determine the value of differently sized populations. The aim of this handbook is to shed light on the value of population change and the nature of our obligations to future generations, and to offer practical guidance to policy-makers as to how our duties to future generations should be discharged. It contains an extensive and accessible introduction for those unfamiliar with the topic of population ethics as well as original work from key figures in academic debates on population ethics covering three main themes: (1) ways out of the paradoxes of population ethics, (2) questioning some philosophical and methodological assumptions underlying these paradoxes, and (3) several applications of population ethics to real world issues.