61 4. The authorized cost of individual tickets indicated on a TA is calculated by the UNOG Travel Subunit and therefore the final cost of any ticket is beyond the control of OHCHR. In compliance with United Nations regulations and rules, the best market fare established for the requested travel for experts is in business class, taking into consideration any special purchase agreements negotiated between the United Nations and airline companies. The UNOG Travel Subunit then approves the request and forwards it to the United Nations travel partner, currently Carlson Wagonlit (CWT), which issues electronic tickets. The itinerary and the electronic ticket will be communicated via e-mail by CWT. It is essential that the expert carefully reads through this documentation as vital information on visa/transit visa, etc. will be indicated. It is the expert’s responsibility to comply with the instructions (and obtain appropriate visas/transit visas) and respond to CWT in order for the ticket to be issued. In line with the Secretary-General’s mandate to improve efficiency and reduce costs, the Secretariat of the United Nations has implemented an advance purchase policy which requires that all official travel requests purchased by the United Nations are ticketed at least 16 calendar days prior to departure. It is therefore of the utmost importance that the expert confirms the issuance of the ticket as soon as possible, as ticket prices constantly change and usually increase closer to the date of departure. 5. In order to improve the services to experts, a dedicated CWT travel agent has been appointed to deal exclusively with experts’ travel. The agent can be reached by e-mail (unogvip.ch@contactcwt.com) or by phone (+41 22 917 47 43). More information about this service is provided in the invitation letters sent to experts. 6. The United Nations regulations and rules provide that travel must be via the most economical and direct route. The best value and most economical business class air ticket cost is not fixed, and may change from day to day depending on availability. Quoted airfares are thus subject to change and cannot be guaranteed until the reservation is made and the ticket is issued. Neither the United Nations nor the traveller can choose one airline over another, as it is obligatory to use the ticketing arrangement which provides the best value to the Organization. Experts may request to utilize a specific airline or itinerary, but any costs in excess of the approved itinerary must be borne by them personally (see also sect. C below). In cities like New York, itineraries via JFK or Newark may be authorized depending on what is most cost-efficient.