The article introduces a comparative democracy assessment tool, the Immigrant Inclusion Index (IMIX). Our concept specifies the electoral inclusion of immigrant residents as having two constitutive dimensions and meanings for a comprehensive evaluation: 1) de jure: assessing the laws regulating the immigrants’ access to citizenship and alien voting rights in light of the normative demands; 2) de facto: counting the number of people who are actually in- or excluded with respect to both means of inclusion. Since both of these dimensions are necessary for a political system to qualify as electorally inclusive, the potential for substitution is limited. We thus apply the geometric mean, as illustrated in the concept tree below, to aggregate the dimensions. For the two pathways to electoral inclusion, access to citizenship and alien enfranchisement, we apply a weighted arithmetic mean. Description of the index components: * de jure access to citizenship = selected EUDO CITLAW indicators // ius soli – naturalization – multiple citizenship // [0-100 – ordinal scale] * de jure alien enfranchisement = selected EUDO ELECLAW indicators with adjustments in aggregation // active suffrage for non-citizen residents in legislative and presidential elections, and referenda – national and local levels // [0-100 – ordinal scale] * de facto access to citizenship = selected Eurostat indicators // (a) citizenship rate = adult citizens / (adults citizens + NCRallt) // [0-100 – ratio] // (b) naturalization rate = citizenship acquisitions / NCRallt // [0-100 – ratio scale] * de facto alien enfranchisement = autonomous data collection // enfranchisement rate = enfranchised aliens in legislative elections / NCRallt // (national and local electorate, specifically weighted) // [0-100 – ratio scale] NCRallt = Non-Citizen Residents adult legal long-term (estimation with Eurostat and ESS) Before aggregation, the de jure components and the de facto sub-components are normalized. The minima and maxima are adjusted for the citizenship rate [90-100] and the naturalization rate [0-10].