R technologies are creating a vast range of new opportunities to use computers as training tools. As the cost of these technological advances declines, the potential of advanced computer-based technologies for training must be examined. To date, the cost of sophisticated computerbased technologies has constrained their use primarily to situations in which the current training is extremely costly (e.g., current training requires a high fidelity physical simulation or expensive actual equip ment) or in which student errors during training have severe consequences (e.g., where a mistake could result in serious injury or extensive damage to equipment). In this chapter we will focus on two such technologies, intelligent tutoring systems and virtual reality systems, and discuss their potential as training tools. Other related topics, such as the use of high fidelity physical and nonimmersive computer-based simulations (e.g., flight simulators) in training, computer-based or computerassisted instruction systems, and human factors issues associated with the design of user interfaces (e.g., display design) have been addressed by others (e.g.