- American Public Transportation Association provides links to research on current and proposed light rail systems.
- Light Rail Transit Association Information and campaigning about better public transport through trams, tramways, streetcars and light rail transit systems.
- National Corridors Initiative A group focussed on rebuilding infrastructure and restoring Rail to its rightful place in the "rail-highway-air triad". Their excellent newsletter is called "Destination: Freedom".
- Passenger Rail Oklahoma If you want to keep up with passenger rail matters in Kansas, Oklahoma and Texas, consult these people.
- Railroad Workers United RWU is devoted to the rights and welfare of railroad workers, to greater Rail safety, and to the relationship between these and society at large. For example, they are opposed to one-person crews on giant freight trains.
- RUN Rail Users Network, a national passenger rail advocacy group.
- TEMPO Texas Eagle Marketing and Performance Organization
- The Light Rail Now Project is a charitable educational enterprise designed to support efforts both within North America and worldwide to develop and improve light rail transit (LRT) and other rail transit and mass transportation systems.
- The Surface Transportation Policy Project (STPP) diversified transportation system.