New Jersey Certification of Service is a document issued by a court in the New Jersey court system that certifies the service of process on a particular party in a lawsuit. It is used to verify that the person being served with a legal document was actually served with the document and that the service of process was done according to the law. There are two types of New Jersey Certification of Service: personal and substituted. Personal service requires the person being served to be personally served with the document. Substituted service requires the document to be served on a responsible member of the party being served, such as a family member, business partner, or attorney.