The most severe consequences of climate change will accrue to the poorest people in the poorest countries, despite their own negligible contribution to greenhouse gas emissions. In recent years, global health efforts in those same countries have grown dramatically. However, the emerging scientific consensus about climate change has not yet had much influence on the routine practice and strategies of global health. We review here the anticipated types and global distribution of health impacts of climate change, discuss relevant aspects of current global interventions for health in low-income countries, and consider potential elements of a framework for appropriately and efficiently mainstreaming global climate change-mitigation and -adaptation strategies into the ongoing enterprise of global health. We propose a collaborative learning initiative involving four areas: (1) increased awareness among current global health practitioners of climate change and its potential impacts for the most disadvantaged, (2) strengthening of the evidence base, (3) incorporation now of climate change-mitigation and -adaptation concerns into design of ongoing global health programs, and (4) alignment of current global health program targets and methods with larger frameworks for climate change and sustainable development. The great vulnerability to climate change of populations reached by current global health efforts should prompt all concerned with global health to take a leading role in advocating for climate change mitigation in their own countries.