This dissertation focuses on the issue of registration of foreign residents (EU and non-EU) for the 2012 local elections in Belgium. The goal of this study is twofold. First, it aims at identifying and analyzing the factors explaining variations in foreigners’ registration between municipalities. The second objective is to understand how and why these explanatory factors have an impact on their decision to register. A mixed-methods approach is used to provide a broad and comprehensive picture of the registration of foreign citizens. It is assumed that foreigners’ registration rates for municipal elections vary according to the formal and discursive political opportunities at the local level. I also argue that the political opportunities approach needs to be combined with other predictors that are specific to migrant groups. The quantitative results indicate that the presence of a left-wing mayor in the municipality displays a strong positive and significant association with both EU and non-EU registration. Moreover, the results provide a strong support for the hypothesis relating to outreach actions: municipalities organizing many foreign voter outreach actions are more likely to achieve high foreigners’ registration rates than municipalities that organize no action or only a limited number. In addition, the findings show that foreigners’ registration does not depend only on political opportunities, but also on specific characteristics of foreigners relating to their migration process. First, the residential instability has a negative impact on both EU and non-EU registration. Second, municipalities with a high percentage of non-EU residents with the nationality of a country where one of the languages spoken is French or Dutch are slightly more likely to achieve high registration of non-EU nationals. It has been shown that political context matters for foreigners’ registration, but several questions emerge about the way it does matter. Based on the statistical results, three typical and three deviant ...