At a time when the utility industry is focusing on products and services that can enhance competitiveness, affordable fossil plant simulators are a welcome technology. In just a few years, these simulators have progressed from being an expensive tool that few utilities could afford to being a technology that many utilities feel they can't do without. Offering a variety of benefits in the areas of fossil plant training and engineering, today's simulators are flexible, effective, and much less expensive than their counterparts in the 1980s. A vigorous EPRI development and demonstration effort has advanced simulators beyond operator issues to a new era of application, ranging from the training of engineers to the design and testing of power plant technologies. And the technologies that have resulted from simulator development and enhancement will have beneficial uses beyond plant simulation.