Seniority usually is the main factor in determining promotion from brake operator to conductor and from the extra board to a permanent position. Advancement to conductor jobs is limited because there are many more brake operators than conductors. Most railroads maintain separate seniority lists for road service and yard service conductors. Conductors usually remain in one type of service for their entire career. On some railroads, however, conductors start in the yards, then move to freight service, and finally to passenger service.
Some conductors advance to managerial or administrative positions.
For subway operator jobs, subway transit systems prefer applicants to have a high school education. Some systems require subway operators to work as busdrivers for a specified period of time. Applicants must be in good health, articulate, and able to make quick, responsible judgments. New operators generally are placed in training programs that last from a few weeks to 6 months. Some operators with sufficient seniority can advance to station managers.