Development of modern tourist industry facilitates access to high altitude for a growing population of non-acclimatized individuals who frequently are unaware of the hazards related to this environment, which is characterized by low ambient oxygen due to low atmospheric pressure. High-altitude related illnesses therefore represent an emerging medical issue, which may become of concern for every practitioner. Three clinical entities are classically described: acute mountain sickness (AMS), high altitude cerebral edema (HACE) and high altitude pulmonary edema (HAPE), the two latter representing vital emergencies. The present paper presents the current recommendations for their diagnostic, prophylactic and therapeutic management.