As service providers compete to roll out advanced end-user services over next-generation networks (NGNs), they must consistently meet accelerating customer performance and service expectations to maintain their competitive edge. A key component in balancing these efforts is the development of a new maintenance model that goes beyond conventional product-level support. This white paper dimensions the two-stage evolution from today’s prevalent productlevel support model to network-level support and ultimately to service-level support. It then details the four key ingredients of the service-level support methodology and reveals and how this methodology provides the tools for seamless end-to-end proactive monitoring and maintenance that optimize service availability, reduce operating costs and allow service providers to focus on service enhancements for revenue growth.