Transnationalism and genealogy is an emerging subfield of genealogy. The field has witnessed a significant growth in the last two to three decades, especially in the areas of transnationalism and family arrangements, transnational marriage, transnational adoption, transnational parenting, and transnational care for elderly parents. However, large gaps remain, especially with regard to the impact of transnationalism on lineage. Articles in this Special Issue fill some of the gaps. Additional research is called for.