Before coming to Duke in 1988, he was on the faculty at Virginia Polytechnic Institute and State University. He has held visiting positions at IUCN--The World Conservation Union, the Economic Growth Center at Yale University, and the Indonesian Ministry of Forestry. He has served as a consultant to the World Bank, World Health Organization and other international organizations. He was named Duke University's Scholar Teacher of the Year in 2004.

Kramer's research is focused on the economics of ecosystem services and on global environmental health. He is currently conducting a study on the effects of human land use decisions on biodiversity, infectious disease transmission and human health in rural Madagascar. Recent research projects have used decision analysis and implementation science to evaluate the health, social and environmental impacts of alternative malaria control strategies in East Africa. He has also conducted research on health systems strengthening, economic valuation of lives saved from air pollution reduction. and the role of ecosystems services in protecting human health.