Project Manager Training Devices (PM TRADE) has committed to an open architecture, component-based acquisition methodology enabled through the Live Training Transformation (LT2) product line, which is built upon a number of open standards & processes. First, LT2 products use the Common Training Instrumentation Architecture (CTIA) to define interoperability standards among training applications to support live training. PM TRADE then developed the Live Training Engagement Composition (LTEC) to provide an open architecture solution for communication for Tactical Engagement Simulation Systems (TESS) components. This flexible architecture will drive innovation and lower acquisition costs by making it possible for systems to operate in the same training environment given an adherence to the LT2 LTEC Interface Control Document. As a result of open standards and a product-line approach, PM TRADE was able to quickly and efficiently develop, field, and operate an instantiation by integrating the open standards, architecture, and applications of the LT2 product line to create the Integration and Development Environment – Forward (IDEF). IDEF (formerly known as L-FITE) is a persistent training environment that enables proof of principle concepts and emerging capabilities to be utilized during Force-on-Force training events for Soldier feedback prior to full implementation into Army “Live� System Programs of Record. This paper will begin by with a brief history of Force-on-Force training. Then, it will describe the concept, process, and strategy for IDEF development and operations. In addition, the paper will document results and lessons learned from a number of testing and integration events leveraging IDEF in a land navigation course use case. Finally, this paper will discuss the framework created for IDEF to evolve to provide a verification and validation methodology for future training systems, inform future Army source selections and Programs of Record (POR), and provide the capability to continually review the relevance of fielded training systems.