Sync field property from contact across to sales order.

Sync field property from contact across to sales order.

We use Leads, Contacts, Sales Orders and Invoices. We have a couple internal companies in the same CRM system. The Contact has a field that designates which internal company the Contact is from, but when we create a Sales Order, the only way to know what company it is for, is by the Sales Order owner (will be the same as the Contact) but people come and go. I want the Contact property designating internal company to map over to the Sales Order???