door.donau-uni.ac.at o:5687 DOI 10.48341/g31s-vq79-07 Register data sources on migrant stocks Key points • Analysing irregular migrant stocks using register or other administrative data can prove challenging given the usually undocumented nature of the phenomenon; yet, some recent efforts highlight the potential of register data. • The German Central Register of Foreigners (AZR) provides longitudinal data on non- Germans staying or having previously stayed in the country, including subsets of irregularly staying migrants, allowing for in-depth analyses of various research questions. • Throughout, the chapter provides real-life examples of how register data has been used in irregular migration research across different countries. eng Register data administrative sources migrants under an obligation to leave toleration Irregular migrant stocks Data integration AZR Germany Duldung 2025-09-30T07:46:56.048Z LOMv1.0 Author BEGIN:VCARD VERSION:3.0 N:Peitz;Laura; FN:Laura Peitz X-ORCID:https://orcid.org/0000-0003-4495-591X END:VCARD https://w3id.org/kim/hcrt/scheme https://w3id.org/kim/hcrt/text Textdokument Text LOMv1.0 yes https://creativecommons.org/licenses/by-nc/4.0 application/pdf 422682 https://door.donau-uni.ac.at/o:5687 https://door.donau-uni.ac.at/api/object/o:5687/thumbnail LOMv1.0 discipline