The MRP Controller in SAP, Material Requirements Planning Controller, is a mandatory field in Material Master.
It represents the person, or group, that will be responsible of controlling the material workflow scheduling.
In order to define a new MRP Controller, go to the SPRO customizing transaction, under Production > Material Requirements Planning > Master Data > Define MRP Controllers
There, the available entries will be displayed, or clicking on the New Entries button will allow the creation of a new one
Enter all the mandatory details : Plant, code, description, business area, profit center, recipient type and recipient
When saving, give a Customizing request number
And voilà ! A confirmation message Data was saved should be displayed