Darby Jack, PhD, studies environmental health risks in developing countries, the health impacts of climate change, and the role of the urban environment in shaping health. He is in the Department of Environmental Health Sciences. For the last several years his primary focus has been the health effects of exposure to indoor air pollution from biomass fuels. With support from the Center for Environmental Health in Northern Manhattan, he has helped to develop a Columbia-wide biomass working group, which coordinates and supports interdisciplinary research on the topic. These collaborations have given rise to current efforts to measure the health benefits of clean cookstoves in Ghana. In New York, he is collaborating with exposure scientists to estimate the effects of air pollution exposures on people who commute by bicycle.