Improving the local and global environment will have immediate benefits for health, welfare and income. The scientific evidence that adverse global environmental change will damage health is accumulating, involving both direct and indirect mechanisms, including the effect of lost livelihoods. Environmental changes will undermine some of the scientific, technological and social progress which has led to the large increase in global life expectancy observed since 1950. Whilst local environmental risks still cause significant impacts on human health and welfare, the biggest threat to global health appears to be from a cascade of future adverse environmental effects. Reducing this risk is vital not just for environmental and ecological integrity, but also to protect future health. Much can be done to promote technologies, policies and lifestyles in order to improve both health and environmental conditions. © 2012.