Translate the following English sentence to French:
"The principal aim is for workers, when they move to another Member State, to be able to transfer their supplementary pension schemes and continue to pay into them without forfeiting their pension rights and with a guarantee that their accumulated pension rights will retain their value."
Le but premier est que les employés, lorsqu' ils émigrent vers un autre État membre, puissent emporter leur retraite complémentaire et continuer à la constituer sans interruption tout conservant la garantie de l' intégralité des droits à la retraite déjà acquis.