A field of applied psychology devoted to technical aspects of the work process, particularly the improvement of methods of work, the working environment, the problem of fatigue, and the design of equipment used by the worker. Although some psychologists restrict the field to equipment design, the current trend in America is to include all these areas. A number of other names have been applied to the field, however, chiefly human engineering, human factors research, applied experimental psychology, ergonomics, biomechanics, and biotechnology.The engineering psychologist works in close collaboration with engineers in developing procedures, equipment and environmental conditions that lead to greater efficiency and satisfaction. As a psychologist, his major contributions stem from his knowledge of human behavior and his experience with experimental methods and techniques. The specific subjects of investigation can be grouped into three categories: (1) working conditions (illumination, ventilation, noise, music); (2) working procedures (fatigue effects, work schedules, time and motion studies, monotony, accident prevention); (3) equipment design (man- machine systems, spatial layout, displays, controls).Although these topics are primarily associated with industrial psychology, many of the investigations apply to other fields as well. Studies of lighting, music, ventilation, and noise have found many applications not only in factories, offices, and stores, but in schools, libraries, and waiting rooms. Considerable research has also been done on extreme environmental conditions, particularly in space travel, underwater exploration, and polar expeditions. Many of the studies of safety and accident-proneness apply not only to accidents in industry but in the home and on the highway as well. Research on equipment design has been extended to the design of military equipment, space vehicles, telephone dials, road signs, traffic lights, and many consumer products such as kitchen appliances.The rapid expansion in industrial and military technology in recent years has brought with it an ever-increasing interest in engineering psychology. The growth of the field is indicated by the fact that there is a special division of the American Psychological Association, the Society of Engineering Psychologists, devoted to this field. Current research is reported in the Association’s Journal of Applied Psychology.