An initial contractor (5) that receives a request from an ordering customer (3) to manufacture a product performs a process edition conference via an outsourcing service using a computer (11) of the initial contractor. The initial contractor (5) receives a request from an ordering customer (3) to manufacture a sheet metal product. For manufacturing the product, the initial contractor (5) performs a processing edition conference to decide the method for processing the product and to estimate the price required and the delivery schedule. In the performance of the processing edition conference, the initial contractor (5) requests the services of an outsourcing service center (7). A CAD/CAM operator of the outsourcing service center (7) logs in to a computer (11) of the initial contractor from a computer (13) of the outsourcing service center, such that the operator participates in the processing edition conference while operating the computer (11) of the initial contractor, so that the processing method, price estimate and delivery schedule are decided by work performed on the computer (11) of the initial contractor.