The Joint Vision 2020, which guides the continuing transformation of America's armed forces, states "Interoperability is the foundation of effective joint, multinational, and interagency operations." Most of us have our own ideas on the difference between the terms interoperability and integration when it comes to systems, and probably tend to use them interchangeably and incorrectly. This paper explores the difference between the two terms within the context of an Army System of Systems (SoS) training product called the Live, Virtual, Constructive Integrated Training Environment (LVC ITE), and its integrating architecture and infrastructure. The Live, Virtual, Constructive - Integrating Architecture (LVC-IA) is a U.S. Army Program Of Record (POR) intended to provide a two-way network-centric linkage between models, simulations, instrumentation, and Mission Command (MC) systems supporting collective and battle staff training and mission rehearsals for a Brigade Combat Team (BCT). This paper examines how the systems, or components, within the LVC ITE SoS domain exchange information and how that information is used. The paper also describes how the LVC-IA POR performs the act of integration by coordinating and blending disparate pieces into a functioning and unified system. Key pieces of this integration and interoperability use case include simulations such as the Joint Land Component Constructive Training Capability (JLCCTC) Entity Resolution Federation (ERF), the Homestation Instrumentation Training System (HITS), the Close Combat Tactical Trainer (CCTT), and the Aviation Combined Arms Tactical Trainer (AVCATT). The paper will also examine how pieces of the LVC-IA POR, such as Cross Domain Solution (CDS), Gateways, Agile Development Methodology (ADM), and product-line engineering approach, are integrated to meet an architectural objective. Lastly, lessons learned from a SoS Engineering perspective are presented in addition to a way ahead on LVC-IA compliance with the Army Common Operating Environment (COE).