Update Owner on multiple companies and contacts

Hi

We are using CRM 2011 online.

We are currently reassigning accounts and contacts to match the new territory assignments.

Is there a quick way to reassigning the owner of multiple records at one time.

I've tried edit replace and workflow to reassign the owner, but the owner field in each case is not a selectable field.

Any suggestions?

Thank you

Ellen

ellen.bothe@emerson.com