In central Niger certain Ful'be pastoralists challenge assumptions of the inevitable sedentarization of mobile peoples. Participant-observation in Tanout arrondissement, Republic of Niger, suggests that in the past two decades some sedentary households have desedentarized, giving up cultivation for a purely pastoral, mobile livelihood. This research investigates specific reasons for, and processes involved in a livelihood transition from sedentary agropastoralism to mobile pastoralism, concentrating on the differential effects of this transition based on gender and age. Grounded in theories of entitlement, agency and household economics, the research hypothesizes that the transition to mobile pastoralism is a rational choice negotiated within households as a risk management strategy in an effort to improve livelihood security, and that the livelihood transition has affected women and men differently. The research uses a mixed methods approach in a comparative study of 40 newly mobile pastoral households and 40 sedentary households. It employs household surveys, GPS mapping, group interviews, in-depth individual interviews, and comprehensive participant-observation. Surveys and in-depth case studies will collect data on asset exchanges, social network links, geospatial mobility, and the economic activities, decisions and perspectives of individuals within households. This research will contribute to anthropological understandings of the ways in which mobility, social networks, individual agency and local knowledges maintain or improve livelihood security, and how gender and age operate in processes of livelihood change in a dynamic and risky environment. Desedentarized households contest received notions of nomadism held by government and development administrators. This research joins a growing body of literature that explores indigenous knowledges and relationships to environments, challenging "expert" knowledge inherited from colonial administrations.