The U.S. Army Simulation Training and Instrumentation Command (STRICOM) is involved with transitioning many simulations to the High Level Architecture (HLA). To coordinate efforts and share lessons-learned, several major STRICOM programs have joined together to create the STRICOM Federation. The STRICOM Federation will be comprised of federates representing a variety of real-time, platform-level training applications such as an Rotary Wing Aircraft (RWA) simulation, Close Combat Tactical Trainer (CCTT) manned module, CCTT Semiautomated Forces (SAF), and Modular SAF (ModSAF). Each of the participating federates provide an example legacy system migrating to the HLA. Using the Federation Development and Execution Process (FEDEP) model as a guide, the STRICOM Federation will integrate the respective federates and move toward achieving interoperability in an HLA federation execution. Commercial and government tools will be used to help achieve federation objectives. This paper will describe the lessons learned in the development of the STRICOM Federation. The application of tools and where they can best be used in the FEDEP process will also be evaluated.