Master- and Reference Data entities must be securely managed and quality controlled by an accountable Data Steward across the complete lifecycle. Controlled Change: At any given point of time, Master Data values should represent the organization’s best understanding of what is accurate and current. Matching rules that change values should beapplied with caution and oversight. Any identifier merged or split should be reversible. Changes to Reference Data values should follow a defined process; changes should be approved and communicated before they are implemented. Stewardship: Business Data Stewards are accountable for controlling and ensuring the quality of Reference Data.