"Our true nationality is mankind."
H. G. Wells
Many permanent residents choose to apply for naturalisation in order to gain the significant advantages of a German / EU citizenship. German citizenship entitles to the right to free movement of persons within the EU and all other EU citizenship advantages.
A lawful permanent resident that has resided continuously in Germany for the previous 8 years may apply for naturalisation. Generally, the applicant has to accept the democratic constitution of the country, be able to sustain a living without state support, demonstrate an understanding of the German language, including the ability to read, write and speak words in ordinary usage in the German language and renounce his or her previous citizenship. An applicant is also required to demonstrate knowledge of the fundamentals of the history, principles and form of government of Germany. Different provisions exist for spouses of Germans and former German citizens.
German citizenship favours the principle of ius sanguinis, which means that children of German parents automatically become German citizens notwithstanding their place of birth. Consequently, a birth in Germany of non-German parents may only lead to a German citizenship of the child if its parents have been permanent residents in Germany since eight years.
As Germany generally opposes dual citizenship, German nationals who wish to acquire a second citizenship will need a permit to keep their German citizenship when being naturalised by another country. The so-called "Beibehaltungsgenehmigung" has to be applied for within two years before the new citizenship is acquired.