Talking with air traffic controllers and watching them work will provide you with a strong introduction to their day-to-day activities. Speaking with aircraft pilots may provide other insights into the role of the air traffic controller. Visits and interviews can be arranged through most airports, air traffic control centers, the Air Traffic Control Association, and many airlines. You should also be aware that every branch of the military services offers opportunities for experience in these and related jobs.

Air traffic controllers work in one of three areas: airport traffic control towers, en route air traffic control centers, or flight service stations. The Federal Aviation Administration (FAA), which regulates all air traffic, employs almost every air traffic controller in the United States. Some private airports employ their own air traffic controllers; others are employed at military airports.

Terminal air traffic control specialists are stationed in airport control towers or the terminal radar approach control (TRACON) room. They are sometimes known as tower controllers. They are responsible for all air traffic entering, leaving, or passing through the airspace around the airport, as well as conducting airplane traffic on the ground. These controllers use radar and visual observation to maintain safe distances among aircraft, and they provide information on weather and other conditions to the pilots under their control. As an airplane prepares for departure, the ground controller issues taxiing instructions to bring it to the runway. A local controller contacts the pilot with weather, wind, speed, and visibility conditions and clears the pilot for takeoff. A departure controller monitors the aircraft on radar, maintains radio contact with the pilot until the aircraft has left the airport's airspace, and hands over control of the plane to an en route control center.  (Radar approach controllers are responsible for guiding incoming planes into the airport.) A radar controller monitors the traffic above the airport and into the aircraft's flight route, communicating with the other controllers. Approaching aircraft are handled in a reverse procedure. When many aircraft are approaching the airport at the same time, the controllers arrange them in a holding pattern above the airport until they each can be cleared to land.

There are 518 airport traffic control towers in airports across the country. At a small airport, an air traffic controller may be expected to perform all of these functions. Controllers at larger airports usually specialize in a single area. Senior controllers supervise the activities of the entire center. Terminal air traffic controllers may be responsible for all aircraft within as much as a 50-mile radius of their airport. Most controllers are responsible for many aircraft at once; they track their positions on the radar screen, receive instrument flight data such as an airplane's speed and altitude, coordinate the altitudes at which planes within the area will fly, keep track of weather conditions, and maintain constant communication with the pilots and with controllers at their own and other control centers. An air traffic controller must be aware of all of the activities in the air traffic control center and around the airport. When an aircraft experiences an emergency, air traffic controllers must respond quickly, clearing a path for that aircraft through the traffic, alerting fire and rescue teams, and guiding the pilot to a safe landing.

En route air traffic control specialists work at one of 22 air route traffic control centers in the United States. They coordinate the movements of aircraft between airports but out of range of the airport traffic controllers. Because an en route center may be responsible for many thousands of square miles of airspace, these controllers generally work in teams of two or three, with each team assigned a particular section of the center's airspace. Each team consists of a radar controller, the senior member of the team, and radar associates. A center may employ as many as 700 controllers and have 150 or more on duty during peak flying hours. Within the center's airspace are designated routes that the aircraft fly. En route controllers monitor traffic along those air routes. They use radar and electronic equipment to track the flights within the center's airspace and to maintain contact with planes within their area, giving instructions, air traffic clearances, and advice about flight conditions. If flight plans for two airplanes conflict, the en route team will contact the team responsible for the preceding section in order to change one plane's flight path. The controllers will also coordinate changes in altitudes and speeds among pilots. En route controllers receive or transfer control of the aircraft to controllers in adjacent centers or to an airport's approach controller as the craft enters that facility's airspace.

Flight service station air traffic control specialists make up the third group of controllers. They provide preflight or inflight assistance to pilots from three locations in Alaska that are linked by a communications system. These controllers give pilots information about the station's particular area, including terrain, weather, and anything else necessary to guarantee a safe flight. They may suggest alternate routes or different altitudes, alert pilots to military operations taking place along certain routes, inform them about landing at airports that have no towers, assist pilots in emergency situations, and participate in searches for missing or overdue aircraft.