The requirements for performance of VR systems vary for different application domains. Likewise, there are various technological options to achieve each of the requirements. Therefore, an early evaluation to determine optimal configuration of VR systems based on domain specific requirements for simulations and interactions is of immense value. In this paper, the authors have demonstrated the use of systems engineering, particularly Model-Based Systems Engineering (MBSE), to describe a complex decision space in Virtual Reality development. Further, the authors then employed a descriptive decision analysis framework to identify suitable configurations to enable VR development. MBSE is used to develop descriptive models to specify needs of the application domain, requirements of the VR system and to define the system architecture – functional and physical. This will serve to demonstrate how MBSE can be used to generate information to improve decision making for VR designers as well as engineering managers and decision makers. VR application in emergency response training is the exemplary case considered in this paper.