To demonstrate an understanding of the travel department's needs, the CPO should take a holistic approach, focusing on both supply and demand aspects of travel services. This involves understanding the various suppliers (airlines, hotels) and the internal demand factors (company travel policies, different classes of travel). By optimizing both supply contracts and internal demand management, the CPO can develop strategies that control costs while meeting the company's travel needs effectively. This approach shows a comprehensive understanding of the complexities involved in managing travel services.References:

Procurement and Supply Chain Management by Kenneth Lysons and Brian Farrington.

Travel and Expense Management Best Practices by Aberdeen Group.