Simulation games serve many functions, but the important one to educators is that they present the student player with a real-life situation allowing him to use his knowledge and abilities while discovering decision-making skills for himself. To provide a basic reference on simulation gaming, essays on various aspects of games were collected from people responsible for the development of the technique. The rationale for the use of games in education is found in examining how social processes can be simulated and what educational objectives can be presented in this way. The potential impact that games can have is indicated in examples from research, including results from single game sessions showing effects on factual knowledge, attitudes, and strategies and results of longer games that were compared to conventional methods. The parameters influencing the effectiveness of games include learner characteristics: age, social status, intensity of participation, personal predispositions, and achievement level, as well as characteristics of game advisors. Other parameters are the way that a game is administered and whether competition is individual or group oriented. Finally, the effect of the future on the use of games is considered. A listing of centers working on educational games and a selective bibliography are appended. (MT)