Pré-publication, Document de travail: This paper investigates the importance and role of migration networks in Senegal using a new nationally representative survey conducted in 2006-2007. Using a sample of 1707 Senegalese households I explore potentially differential effects of networks on international migration depending on their characteristics in terms of composition and destination. Results from logit and multinomial logit regressions show that household networks seem to be destination-specific and have a greater positive influence on migration than community networks. Networks also seem to have heterogeneous effects on migration depending on gender, household wealth or size which is consistent with previous findings in the literatureand backs up a networks effects story.