Amtrak Cascades and Sound Transit Sounder trains share stations in Everett, Edmonds, Seattle, and Tukwila. At these stations, passengers can switch between Amtrak Cascades and Sounder commuter trains.
Amtrak Cascades Intercity Passenger Rail is sponsored by ticket-buying passengers, the states of Washington and Oregon, and Amtrak. Amtrak Cascades operate on the same railroad tracks as freight trains, makes a limited number of stops, and connects central cities between Vancouver, British Columbia and Eugene, Oregon.
Commuter Rail trains provide passenger service between central cities and their suburbs. Commuter rail trains typically operate only on work days and during commute hours. Most riders make trips of less than 50 miles for work, school, or errands. These trains typically run on the same railroad tracks as freight trains and often share some stations with Amtrak intercity trains. Washington State works with local communities to study the potential for new commuter rail service.
- Sound Transit's Sounder Commuter Trains are sponsored by Sound Transit and ticket-buying passengers. Sounder offers commuter rail service between Tacoma and downtown Seattle with stops in Puyallup, Sumner, Auburn, Kent, and Tukwila, and between Everett and downtown Seattle with stops in Edmonds. It shares the same railroad tracks as freight trains and Amtrak. In contrast to intercity passenger rail (Amtrak), Sounder commuter rail makes frequent stops along the 70-mile corridor between Everett and Tacoma, with service currently provided only during the weekday morning and evening commute hours. Sounder commuter trains make additional stops along the route at Auburn, Kent, Sumner, Puyallup, and Tacoma's Tacoma Dome station. Future Sounder service will add stations at Mukilteo, South Tacoma, and Lakewood.
- Sound Transit Link Light Rail offers service between downtown Tacoma and the Tacoma Dome, a distance of less than two miles. Rides on Tacoma Link are free and Sound Transit pays for operations. Link trains run every 10 minutes. Unlike Amtrak Cascades and Sounder trains, Sound Transit's Link light rail trains run on their own set of tracks; they do not share right of way with any other trains.
- Sound Transit's longer Central Link is scheduled to begin service in 2009 in downtown Seattle, and residential and commercial neighborhoods in Beacon Hill, the Rainier Valley, Tukwila, and the city of SeaTac. Sound Transit, the federal government, and others are providing money to build the Central Link light rail system in Seattle.
Light Rail refers to the number of riders that the train can carry, not the weight. Light rail trains provide passenger service within a city and its suburbs. They operate on their own tracks—they don't share tracks with commuter rail, Amtrak, or freight trains—but sometimes share right-of-way with automobiles. They also run at frequent intervals and typically run not only in commute hours but also during the day, weekends, and evenings.
Monorail is railway having a single track for passenger or freight vehicles. In most cases, the rail is elevated. Washington State's only example of a monorail is the Seattle Center Monorail .