This standard serves as instruction for planning@ steering@ and implementing the reliability improvement of products as well as for monitoring a product??s reliability during its in-service phase. The reliability improvement procedure ensures that the specified reliability goal (VDI 4007) or other agreed goals are actually achieved. The standard covers the following topics: recording of faults and analysis of the troubleshooting process for the purpose of improving a product??s reliability. It does not describe the process driven by the desire for functional enhancements and other product optimization goals (e.g. maintenance@ costs@ production processes@ ergonomics@ observation of competing products) even though these goals are related to some extent to this standard. Within the meaning of this standard@ reliability improvement is considered to be a process. The organisation is responsible for implementing this process. This standard outlines the fundamentals of monitoring and assessing the reliability of a product during its in-service phase@ thus enabling the organisation to trigger any reliability improvements which may be required. The required process is described below along with suitable methods and procedures for implementation. This standard only deals with reliability improvement for an existing product. It does not cover product optimisations which do not affect reliability parameters or functional enhancements.