Wildlife conservation in the UK is based on three main actions: landscape-scale protection of habitats, species protection, especially of rarities, and site management to maintain viable ecosystems. None of these addresses human population issues, and policies to deal with population growth vary around the world. Disturbingly, in many developed countries, there is concern about declining human numbers, and attempts are underway to promote larger families. With greater foresight, the developing world is in many cases trying to curb growth, even in countries with lower population densities than in western Europe. At the time of writing, Britain has no policy on population, and the possible components of such a policy are discussed. It will be important to maintain current small average family sizes, but most critical will be a humane but effective control of immigration. In the long term, this will be key to reversing wildlife declines in the UK.