First of all I would like to mention about Air Traffic Services. Air Traffic Control Service ATC. Aerodrome Control Service Approach Control Service Area Control Service Flight Information Service Alerting Service Flight Advisory Service These are the main ATS services. Then I would like to describe about main goals of ATS. a) Prevent collisions between aircraft; b) Prevent collisions between plane on the maneuvering area and obstructions on that area; c) Expedite and maintain an orderly move of air traffic; d) Provide advice and information useful for the safe and effective conduct of flights; e) Notify appropriate organizations regarding plane looking for search and rescue aid, and assist such organizations as required. (ICAO 2013) Prevent collisions between aircrafts.