The proposed study examines the impact of the Chad-Cameroon Petroleum Development and Pipeline Project on household economies, production activities, decision-making, and health in Chad. The Pipeline Project is a joint undertaking of the governments of Chad and Cameroon, the World Bank, and a consortium of oil companies headed by ExxonMobil. At a cost of $3.7 billion, it is the largest construction project on the African continent. The Project has drawn considerable attention, not only for its size, but also because of the terms and conditions of engagement agreed upon by the three principal actors in regard to health, the environment, and assistance to local communities. The World Bank, as a condition of its participation in the Pipeline Project, stipulated that the government of Chad earmark approximately 70% of its revenues from the Project for investments in health, education, and rural and infrastructure development. Further, the consortium was required to conduct an environmental impact assessment and to prepare an environmental management plan that includes provisions for social and economic programming to mitigate the effects of the Project on local population. Many previous investigations of the impact of large-scale infrastructure projects on local communties have been narrowly conceived, focusing on a particular sector or aspect of change; have privileged the use of aggregate data or summary indicators; and have been retrospective in character. This two-year study will lay the groundwork for a longitudinal, panel study of the impact of the development of the Pipeline Project on households. That research will be carried out by prospectively following at least 120 households from localities that differ in terms of their proximity to the Pipeline Project; their productive base; their access to health care services; and their integration into a cash economy. Households will be followed through the construction phase (anticipated to reach completion by 2004) and into the exploitation and revenue-generating phase of the Project. The research involves the collection of survey data, narratives on therapeutic regimens, anthropometric data, and water quality testing. The study also brings together a multi-disciplinary research team from medicine, public health, political science, economics, environmental sciences, and nutrition, from Chad, other parts of Africa, and the United States. Capacity-building is an integral part of the proposed work.