The abstract should state the main research question, the context and its relevance in terms of policy issues/needs in relation to PAGE thematic foci, complete with a brief description of the data that will be used. We examine whether increasing self-employment opportunities for rural households benefit or not the smallholder farm sector through investment linkages in Niger. Off-farm activities are viewed as an important source of cash income, which can potentially improve farm productivity if it is used for farm input purchase. There is the argument that, negative externalities might however result from the expansion of off-farm activities through the existence of factors that are share across farm and off-farm activities. We first examine factors that determine farm households? decisions to involve into self-employment activities and then analyse the impact of that decision on farm households? agricultural production, on agricultural inputs used and on food security. Many studies in a similar context as in Niger have stressed the importance of understanding the constraints face by the rural non-farm sector and its implications. Yet in Niger there is little knowledge if not any on the determinant of low-skilled off-farm employment and the nature of the linkage between the farm and the non-farm sector resulting from the increasing of such non-earned work. We use the data from the Enquête Nationale sur les Conditions de Vie des Ménages et l?Agriculture de 2011(ECVM/A- 2011), available online in the World Bank site. The ECVM/A is implemented by the Niger Institut National de la Statistique (INS) and is nationally representative. We make use of the endogenous switching regression model (ES) accounting for the argument of technical interdependencies or jointness between on- and off-farm activities, and for the potential endogeneity of self-employment involvement.