The core of most Master Data Management (MDM) solutions is a master data hub. MDM solutions as those appearing in analyst reports revolves around a store for master data that is a new different place than where master data usually are. That is for example being in CRM, SCM and ERP systems.
For large organizations with a complex IT landscape having a MDM hub is usually the only sensible solution.
However for many midsize and smaller organizations, and even large organizations with a dominant ERP system as well, the choice is often naming one of the application databases to be the main master data hub for a given master data domain as customer, supplier, product and what else is considered a master data entity.
There are arguments for and against both approaches. The probably most used argument against the MDM hub approach is that why you should solve the issue of having X data silos with creating data silo X + 1. The argument against naming a given application as the place of master data is that an application is built for a specific purpose and therefore is not good for other purposes of master data use.
Where do you put your master data? Why?