This chapter examines the strategic importance of the Installed Base (IB) as a vital asset for Original Equipment Manufacturers (OEMs), highlighting its role in enhancing sustainability, operational efficiency, and customer engagement. The IB, which includes all operational machinery sold by an OEM, acts as a foundation for service-oriented business models, facilitating predictive maintenance, customized service contracts, and long-term customer relationships. By leveraging IB data, manufacturers can optimize service delivery, anticipate customer needs, and drive innovation through tailored offerings. This shift from product-centric to service-driven strategies extends product lifecycles, reduces waste, and promotes resource efficiency, reinforcing sustainability objectives. Moreover, integrating advanced analytics and customer relationship management (CRM) systems enhances strategic decision-making, allowing firms to maximize value creation and maintain a competitive advantage. The chapter emphasizes the necessity of a structured approach to IB management, illustrating how it supports servitization, financial growth, and environmental stewardship in contemporary industrial ecosystems.