This is the fourth in a series of reports that T2RL has produced during the course of 2023 on the transformation to the new Offer, Order, Settle, Deliver environment. This particular report considers the impact of the changes on those organisations that sell on behalf of the airlines. These are primarily travel agents of various kinds, including the large Online Travel Agencies (OTAs), the major Travel Management Companies (TMCs) and the retail travel agencies that serve a mix of business, leisure and inclusive tour travel.