When the design has been released for production, tools have been pro- cured, and materials, parts, and components have been received, product control, the third job of quality control, comes into play. Product control involves the control of products at the source of production so that departures from quality specifications can be corrected before defective or nonconforming products are manufactured. It not only involves the materials and parts themselves but control of the processes that contribute the quality characteristics during the manufacturing operation. It seeks to deliver a reliable product that will perform satisfactorily during its expected life and under the conditions of use. It therefore also involves quality activities after production and in the field and product service, which assures the consumer recourse in obtaining the intended product function, should recourse be necessary for any reason.