A dispatcher is a communications worker who receives and transmits information to coordinate operations of other personnel and vehicles carrying out a service. A number of organizations, including police and fire departments, emergency medical services, motorcycle couriers, taxicab providers, trucking companies, railroads, and public utility companies, use dispatchers to relay information, direct personnel, and coordinate their operations. Types of dispatchers Emergency dispatchers An emergency dispatcher, also known as public safety dispatcher, 9-1-1 dispatcher, or public safety telecommunicator receives calls from individuals who require emergency services, including police services, firefighting, and emergency medical services. Once information is obtained from the caller, the dispatcher activates the appropriate services necessary to respond to the nature of the call for help. The dispatcher also obtains and relays pertinent information to the field units to help ensure the adequacy and safety of the response. Emergency dispatchers may also use preapproved protocols to talk a caller or bystander through lifesaving medical procedures such as cardiopulmonary resuscitation, childbirth, and first aid. They may also require special certification. In the United States, about 10% of all dispatchers employed in 2004 were public safety dispatchers. Transportation and service dispatchers A number of other organizations use dispatchers to respond to service calls, coordinate transportation schedules, and to organize the delivery of materials: A truck dispatcher is employed by a trucking company to monitor the delivery of freight over long distances and coordinate delivery pickup and drop-off schedules. A bus dispatcher monitors the schedules of their bus fleet and address any problems that arise during their operations. A tow-truck dispatcher responds to calls for emergency roadside assistance. A gas and water service dispatcher monitors their respective utilities and receive calls for emergency assistance that involve gas lines and water mains. In the United States, about 26% of all dispatchers employed in 2004 worked for transportation and warehousing industries. Railroad dispatchers A train dispatcher is employed by a railroad to direct and facilitate the movement of trains over an assigned territory, which is usually part, or all, of a railroad operating division. The dispatcher is also responsible for cost effective movement of trains and other on-track railroad equipment to optimize physical (trains) and human resource (crews) assets. A crew dispatcher is also employed by the railroad to keep track of train crews and their assignments. The crew dispatcher is responsible for assigning train crew to trains based upon scheduled rosters, and also