International shipping of vaccines is the first leg of the complex journey that vaccines undertake to reach the end users in a country. Particular challenges include the size and weight of packages, implementation of quality control checks at reception, ensuring environmental sustainability, and maintaining required temperatures during the journey. Although there are many possibilities of transport e.g. sea freight and terrestrial transportation, air freight currently remains the most widely used means of transport for vaccines. In recognition of this fact, these guidelines apply predominantly to the air freighting of vaccines. Transportation of vaccines from the manufacturing facility to the airport facility require the use of ground transportation, and reference is also made to the qualification of refrigerated road vehicles as well. The objective of these guidelines is to provide technical guidance to help ensure the quality of vaccines during all stages of the international air transportation process. These guidelines are applicable to all persons and institutions involved in international air shipment of vaccines from the premises of the product manufacturer to the recipient country. This includes all parties involved in shipment, vaccine manufacturers, logistics service providers (LSPs), freight forwarders, carriers and their employees. The relevant sections of these guidelines should also be considered for implementation by UN procurement agencies and other international procurement organizations, countries, donor agencies and certifying bodies.