It's been said that a database is only as good at the data in it. A good way to insure good data is to reduce the amount of data entry by your users and to insure the correct data is entered. A way to accomplish this is through the mapping of fields from parent records to related, child records.
The key to making the mapping work is that the users need to create the new, child record from the parent record. For example, if you have an Opportunity record open, you would then select Quote from the left navigation and then click the 'Add New Quote' button from the ribbon when it changes.
To setup the mapping, do the following:
Get to 'Customizations'. One way to do this is to go to 'Settings', 'Customizations', and then choose 'Customize the System'.
Select arrow to the left of the parent entity to expose the sub-menu items. In our example, that is the Opportunity.
Once there, go to the Opportunity entity and click on the '1:N Relationships'.
Next click on 'Mappings' and then the 'New' button.
Lastly, choose the source and target fields, click 'OK' and you're done.
An important note here is that the field types must be same on both entities if you want to map fields! For questions and help around Dynamics CRM or Dynamics 365 contact our team.