Sometime you need to add a field from the contact table onto the data entry form. On the screen shot below we are displaying the BILL TO and SHIP TO fields directly from the attached contact. This gives you more flexibility when doing data entry since you can confirm contact information.
2) Using the controls drop down select List - Parent Tables
Using the designer you can add fields from the parent table (contact, company, groups or opportunities) directly onto the data-entry form of the custom record. This parent field will be in read-only mode.