Artificial Neural System (ANS) networks have been successfully developed for a variety of purposes. This WRC Bulletin discusses those for weld bead for weld parameter control; real-time penetration sensing using arc voltage monitoring only; and real-time engine health monitoring. Various ANS models can be combined to provide intelligent control of a welding or manufacturing process. When used appropriately@ ANS is a powerful tool for dealing with real-life control and monitoring problems. Publication of this document - WRC Bulletin No. 397 was sponsored by the Welding Research Council