In this chapter, you've learned how to use Master Data Services to keep one version of the truth. You've seen that MDS provides an extensible modeling mechanism. You can create entities with attributes, a relationship between entities, and also explicit or derived hierarchies based on the existing entities and their relationships. As a master data management service, we can import data into MDS with entity-based staging, and export data out of MDS with subscription views. The next chapter will be about data cleansing with data quality services.