This chapter outlines the German regime for the use of DNA analysis in family reunification cases. It overviews the right to family reunification in German legislation and the role of DNA tests in the administrative process. The chapter presents evidence that DNA testing is increasingly being employed in administrative decision making on family reunification in Germany. It argues that the German legal framing and the administrative practice of DNA testing for family reunification result in a geneticisation of the family. The DNA test serves as a means to verify family relatedness, and proof of biological ties provides a solid basis for administrative reasoning and almost automatically leads to a positive decision on the application. In Germany, the most important piece of legislation with regard to family reunification is the 2005 Residence Act as part of the Immigration Act. The Residence Act, which replaced the Aliens Act, most of the regulations of Council Directive 2003/86/EC and adapted them to national law.