The notion of after action review (AAR) is known in the military where it is used to develop a common picture of what happened and why. Recently, the concept has been rediscovered by other domains. Obviously, a review within these domains would be different. This paper addresses development of an AAR engine. By “AAR engine” we mean a system that provides the common functionalities across all AAR systems into a single foundation for training. Regardless of the domain, there are capabilities needed in an AAR system (e.g. recording and playback of scenario data). On the other hand, there are also features specific for each domain. In this paper we first review the infrastructure of our AAR engine. Then advantages of such a system for addressing various AAR systems are reviewed. Additional advanced functions are then presented and reviewed in light of how the engine can easily provide these enhancements.