Intelligent tutoring systems (ITSs) have shown great promise in military training domains (among others) where they can achieve many of the same benefits as one-on-one instruction, in a cost-effective manner. However, the development of real-world simulation-based ITSs is hampered by the knowledge acquisition bottleneck and difficulties creating instructive simulation scenarios. In this paper we describe an innovative approach to simulation-based ITS development using a case-based reasoning (CBR) paradigm and unique scenario generation techniques that largely circumvent the difficult and time-consuming process of knowledge elicitation. A case-based approach to knowledge gathering is highly intuitive and greatly simplifies training course authoring. Additionally, we describe how the scenarios generated with our approach can offer substantially improved realism and instructional quality through the use of intelligent simulation control techniques.