This paper describes experiences with the evolution of a software maintenance organization for digital set-top boxes of a leading electronics company from a cost center towards a service center. Several years ago a dedicated software maintenance group was constituted. As the costs for software maintenance were not recovered from the customers, the software maintenance group was merely considered a cost center. Through starting a metrics program for software maintenance and defining a service strategy with various service levels, the software maintenance group generated sufficient revenues to become self-supporting. An important conclusion is that the use of ITIL service support has helped to develop a better customer focused approach, which is considered as the most important critical success factor for a professional, self-supporting maintenance organization.