Although games and simulations (in the broadest sense) have been played for amusement for thousands of years, the application of game and simulation techniques to education and training is a comparatively recent development. The use of games as a method of training was first developed for military purposes. Chess, which originates from the sixth century, was perhaps the first war game, but it was not until I798 that games involving the use of maps were used in military training (Thomas, I957). The techniques of war games have since been developed to an extremely high degree of realism and sophistication. It was over I50 years after their introduction into military training that the next major use for games and simulations was developed, namely in business management training. As in military applications, the techniques were used to bridge the gap between formal academic instruction and on-the-job training. In 1956, the American Management Association produced the first business game-a decision-making simulation exercise for potential executives (Riccardi, I957). Since then, the use of such techniques has spread rapidly throughout the western world, and a wide range of exercises, of various degrees of complexity, have been produced at all levels from school to in-service industrial training (Hart, I978). In 1962, gaming and simulation methods were introduced into teacher training, the early exercises taking the form of simulated teaching situations and problems in simulated schools (Hemphill, Griffiths & Frederiken, 1962; Kersh, 1962). Further developments quickly followed in other areas, particularly in the teaching of social studies, geography, international relations and urban development (Walford, 1968; van der Eyken, 1968; Taylor, I97I). During the last decade, however, the techniques have been used in an ever-increasing range of other subjects, including language training, mathematics, engineering and the sciences. It is in this last area that the authors have been working since I973. This article begins by explaining the potential role of games and simulations in science teaching, and then describes some of the exercises that have been developed by the authors. Finally, it explores the possible future role of the micro-computer, and particularly the ways in which the micro-computer and simulations can be used in distance learning.