The  Marine Corps Systems Command (MCSC) and Training and Education Command (TECOM) recognized the need to develop a detailed analytic methodology to justify fiscal decisions for procuring and fielding live-virtual-constructive training environment (LVC-TE) capabilities.  The analytic challenge was a unique endeavor for a complex system of systems with no prior analog identified, and external guidance demanded more concrete analysis and return on investment metrics. The Marine Corps LVC-TE Analysis of Alternatives (AoA) began with  a training and readiness (T&R) based requirements analysis and the definition of a measures of effectiveness hierarchy. This paper will summarize lessons learned from the LVC-TE AoA and the associated methodologies that were developed.  The AoA’s analytic methodology traced capability requirements to the T&R training basis, and the metrics hierarchy captured current training requirements, future training requirements, institutionalization of enterprise capabilities, and compliance with external requirements.  The analysis covered all four elements of the Marine Air-Ground Task Force for both home station training and service level training, linking mission essential tasks with T&R events across collective training audiences. The analysis used workshops, interviews, and briefings for primary stakeholders to gather data. Distinctive, strategic technical alternatives were determined, refined, and assessed against the measures of effectiveness and cost to complete the analytical framework. The technical alternatives spanned a wide range including connecting current Marine Corps systems, using existing LVC solutions across the DoD, and developing a new fully customized solution. Lessons learned from this comprehensive effort have applicability to broader requirements and acquisition audiences requiring analysis of similar training capabilities, and should be applicable to ensuring adaptability of training systems to meet evolving technology capabilities.  The draft AoA final results have been briefed and accepted by the milestone decision authority and TECOM, and MCSC is pursuing procurement actions consistent with the AoA analytic methodology and metrics hierarchy.