To understand what we know and be aware of what is to be known has become the central focus in the treatment of engineering data handling issues. It has been some time since we began treating issues arriving from engineering data handling in a low key fashion because of its housekeeping chores and data maintenance aspects representing nonglamorous issues related to automation. Since the advent of CAD/CAM, large numbers of data bases have been generated through stand alone CAD systems and the rate of this automated means of generating data is rapidly increasing. This possibly is the key factor in changing our way of looking at engineering data related problems. This volume contains some of the papers, including revisions, which were presented at the fourth Automation Technology conference held in Monterey, California. This volume represents ATI's efforts to bring forth some of the important case studies related to engineering data handling from the user's point of view. Because of its potential enormous impact on management and productivity advancement, careful documentation and coordination for outstanding contributions to this area are of utmost importance. This volume may serve as a precursor to additional volumes in the area of engineering data handling and CAD/CAM related user studies. Anyone with comments or suggestions, as well as potential contributors, to this series, is encouraged to contact the editorial board of AT!.