Under the second paragraph of Article 33, the address for service of process must be given in accordance with the law of the State where enforcement is sought. If that law is silent as to when that formality must be completed, it must be completed no later than the date on which the decision authorising enforcement is served. Under Article 33, the consequences of failing to provide an address for service are governed by the law of the State where enforcement is sought - provided that the aims of the Convention are respected.