The travel company is understood to have invited four agencies to pitch for the business next week.
Thomas Cook has used a number of shops on a project-by-project basis, but is now hoping to consolidate its DM into one agency.
The initial brief will see the successful agency produce campaigns for the group's Direct Holidays brand, but future projects will bridge Thomas Cook's other divisions, including the main Thomas Cook brand, Airtours and Cresta Holidays.
The review marks a shift in direction for the company, as it seeks to put greater em- phasis on strategy, as well as placing customer relationship marketing at the core of its below-the-line activity.
The search for a DM agency comes shortly after the appointment of the former Abbey marketing chief An-gus Porter as the company's group strategy director.