Introduction Obsolescence is the st

Introduction Obsolescence is the state which is entered when a component is no longer available in its original form from the original supplier (or it is predicted that it will happen in an estimated time period). Hardware obsolescence results from unavailability of one or more components on different system levels in the final product. Software obsolescence results from changes in demands that make it unsuitable for new requirements coming from changes in hardware or changed/new functional, validation or homologation requirements. The purpose of obsolescence management (OM) is to reduce the consequences of any obsolescence to an acceptable limit. OM is based on an Obsolescence Management Plan (OMP). The OMP contains information regarding obsolescence, relevant plan and potential risk for all relevant components as well as related additional cost and resource requirements needed. Each function has to budget for its own task. The implementation needs to be done carefully evaluating business risk and opportunities. The whole lifetime of a project or product has to be considered and the most economical solution shall be chosen. The upfront investment has to be finally paid off by savings in the later steps and reduction of business risk or by additional business opportunities, such as long spares delivery and service contracts or improved market position to win vehicle contracts. Editorial Remark: The terms system, subsystem and component are used in this document as a notation of hierarchical relation of hardware- / software-items to each other. A system is composed of subsystems which can be broken down to components.