8. The right for every EU citizen, and of his or her family members, to live, to work or to study in any EU Member State is a fundamental aspect of the European Union. Along with other rights provided under EU law, it has shaped the lives and choices of millions of people. Agreeing reciprocal guarantees to safeguard the status and rights derived from EU law at the date of withdrawal of EU and UK citizens, and their families, affected by the United Kingdom's withdrawal from the Union will be the first priority for the negotiations. Such guarantees must be effective, enforceable, non-discriminatory and comprehensive, including the right to acquire permanent residence after a continuous period of five years of legal residence. Citizens should be able to exercise their rights through smooth and simple administrative procedures.