A child support services case can be opened by either parent, or a legal guardian, whether or not a child support court order exists. If you already have a court order, opening a case offers neutral assistance with every part of the process, keeps records, and helps both parties stay on track. If you do not have a case, applying for child support means San Mateo County Department of Child Support Services will help you locate the other parent, establish legal paternity/parentage if required, get a court order and see that it is enforced in every state and many foreign countries. To start the process: