Extreme events, such as severe droughts, flooding, and disease epidemics, are known to result in major social, economic, political, and environmental transformations. The effects may include new constraints on land use and livelihood patterns, altered access to crucial resources, impacts on biodiversity, and long term public health problems. Cumulatively, there are often far-reaching consequences for local and national economies. However, outcomes vary from case to case and surprisingly little is known about why some extreme events result in societal transformation while others of similar magnitude do not. In this project, a team of anthropologists asks the question: Under what conditions do transformations occur as a result of an extreme event?This research focuses on the response of Maasai communities in northern Tanzania to the devastating drought of 2008-2009. The local people claim this drought to be the worst in living memory, stimulating massive migration of livestock and people from southern Kenya and northern Tanzania into neighboring areas in northern Tanzania, with dramatic loss of livestock. The drought was followed by significant changes in land use and traditional institutions and practices, including previously unseen restrictions on who is allowed access to the crucial resources of water and pasture. The researchers will probe why these transformative responses occurred during and following this particular drought but not following previous droughts in recent decades that were equally or more severe. The research will entail ethnographic fieldwork and surveys involving households and village leaders in Maasai villages that were on both the sending and receiving ends of the migration during the drought. The research is designed to reveal how and why responses to the recent drought differed from the past; how the impact of the drought proceeded through a series of phases; and how experiences, decisions, and innovations in one area influenced other areas and, ultimately, the social-ecological system as a whole. The investigators have done research in this area since the mid-1990s and thus have a deep understanding of and detailed baseline data on traditional livelihood patterns and past responses to crises, as well as relationships with local communities that will help ensure accurate assessment of how and why people responded to the drought as they did and what the implications of changing local practices are likely to be. Understanding the responses to extreme events in this case where the situation is well understood and the local-level processes can be identified and followed over time and space will have a direct bearing on planning efforts to cope with the effects of future climatic events and other problems wherever they may occur.