In designing machines and man-machine systems, Human Factors Engineering has generally concentrated upon seeking solutions to physiological problems to enable the human operator to function efficiently. It has, however, neglected the psychological problems, particularly the problems of motivation. This was not too critical as long as machines were “primitive.” With the advent of automation and complex man-machine systems this neglect may have most undesirable effects. An attempt is made to identify the necessary conditions which make a task, per se, motivating. Examples are cited from some new systems where some of these necessary conditions are lacking and the effect of this lack upon the operator is indicated