Healthy children and those with pre-existing conditions traveling to high altitude may experience diverse physiologic changes. Individuals who are not acclimatized and ascend rapidly are at risk of developing acute high altitude illnesses (HAI), which may occur within a few hours after arrival at high altitudes, being acute mountain sickness (AMS) the most common. In very few cases, serious complications may occur, including High Altitude Pulmonary Edema (HAPE) and very rarely High Altitude Cerebral Edema (HACE). Moreover, the number of children and adolescents traveling on commercial aircrafts is growing and this poses a need for their treating physicians to be aware of the potential risks of hypoxia while air traveling. In this article we present 50 years of medical practice at high altitude treating these pathologies succesfully with no casualties.