Anuscheh Farahat and Kay Hailbronner may be lost only pursuant to a law and against the will of the person affected only if he or she does not become stateless as a result. These provisions have been used in order to argue the unconstitutionality of the legislative reform 1999/2000 and particularly the ‘option model’. However, finally, no attempt has been made to challenge the nationality legislation in the Constitutional Court. This may be due to the fact that Article 116 of the Basic Law does provide a relatively broad legislative power to define German citizenship by legislation (for an opinion on the constitutional reform see Hailbronner 1999c: 1273). The implementation process It is within the competence of the Länder to execute federal laws in their own right. Under Article 84 of the Basic Law they are authorised to regulate the establishment of authorities and administrative procedures insofar as federal laws enacted with the consent of the Bundesrat do not otherwise provide such. With the consent of the Bundesrat the federal government may issue general administrative rules (Article 84 para. 2 of the Basic Law). It follows that the Länder may issue administrative guidelines on their own to the extent that there are no federal administrative rules enacted with the consent of the Bundesrat. Since nationality law frequently leaves a wide margin of interpretation, administrative guidelines of the Länder may differ substantially according to the different political aims of the Länder governments. Based upon Article 84 para. 2 of the Basic Law and previously Section 39 of the Reichs- und Staatsangehörigkeitsgesetz 1913 authorising the federal government to issue administrative guidelines with respect to the administrative procedures and the cooperation between the various competent authorities, as well as to formal matters, a number of administrative rules have been enacted since 1950 covering such matters as —the exceptional permit to retain German nationality in case of voluntary acquisition of a foreign nationality; —the acquisition of German nationality by appointment as a German civil servant. A federal administrative regulation of 2000 exists but is meanwhile partly outdated. Due to political controversies between the federal government and the Länder, it has been impossible to adopt a new version ever since. The Guidelines of the Federal Ministry of Interior of 2009 are not binding for the Länder, since formal Administrative Rules can only be enacted by the consent of the Bundesrat. Nevertheless, the administrative courts frequently refer to the non-binding guidelines as administrative practice. 4. Current debates Debates in recent years have mainly concerned the acceptance of dual or multiple nationality. The discussion gained momentum because figures indicated that although dual nationality is meant as an exception to the German nationality law, in practice there has been an enormous increase of naturalisations in acceptance of dual nationality. In 2013, 49.7 per cent (2010: 53 per cent) of applicants who naturalised did not have to renounce to their previous nationality. The requirement of renouncing the former nationality has been exceptionally dispensed with in regard to applicants from Iran, Morocco, Afghanistan, Lebanon and Syria. Furthermore, the former nationality of applicants from the member states of the European Union (for example the UK, Poland, Italy, Greece) was generally accepted. Thus, the legal exception has actually RSCAS/GLOBALCIT-CR 2020/5 - © 2020 Author(s) 31