While family reunification has become a major concern in Europe, with the view that migrants overuse their right to reunite, this chapter shows that Senegalese migrants are largely oriented towards their origin country. Migrants in Europe are predominantly engaged in transnational families, their spouse(s) and/or child(ren) being left behind in Senegal. They thus live transnational lives, involving comings and goings and various sorts of transfers and contacts. This pattern echoes the multi-residential family systems observed that have long been observed within Senegal. Benefiting from the transnational and longitudinal nature of the MAFE data, this chapter challenges the widely shared assumption that family reunification in Europe is the normal path followed by most migrants. The statistical results show that “living apart together” across borders is a long-lasting arrangement for many Senegalese migrants: 10 years after migration, 82% of the married migrants who left their spouses behind are still separated from them; and 88% of those who left a child behind in Senegal are still separated from it. It is quite common for such periods of separation to be ended by reunification at origin (i.e. in Senegal), when the migrant returns. As regards reunification with left-behind children, this is more common than reunification in Europe. On average, migrants who maintain a transnational family life are more vulnerable than other migrants: they are more frequently undocumented, less educated and of lower socio-economic status. In the end, the high prevalence of transnational families appears to be a mixed product of personal (individual or family) choices and policy constraints.