Class I Railroads
·  Burlington Northern and Santa Fe
· Canadian National
· Canadian Pacific Railway
· CSX Corporation
· Ferrocarril Mexicana (Ferromex)
· Kansas City Southern
· Norfolk Southern
· Transportacion Ferroviaria Mexicano (TFM)
· TTX Company
· Union Pacific Corporation 

Regional and Short Line Railroads
· Arkansas & Missouri Railroad
· Anacostia & Pacific Company, Inc.
· BC Rail
· Belt Railway of Chicago
· Canton Railroad Company
· Cedar Rapids & Iowa City Railway Co.
· Chicago, SouthShore & South Bend Railroad
· Conrail Shared Assets LLC
· Dakota, Minnesota & Eastern Railroad
· Durbin and Greenbrier Railroad
· Elgin, Joliet & Eastern
· Emons Transportation Group, Inc.
· Great Lakes Transportation LLC (Duluth, Missabe & Iron Range and Bessemer & Lake Erie)
· Greenville & Western Railway Company, LLC
· Guilford Transportation
· I&M Rail Link
· Indiana Harbor Belt
· Louisville & Indiana Railroad
· Minnesota Central (PioneerRailcorp)
· The Morristown & Erie Railway
· New York & Atlantic Railway
· Nobles Rock Railroad, Inc.
· Ontario Northland
· Pacific Harbor Line
· RailAmerica, Inc.
· Reading, Blue Mountain & Northern Railroad
· Red River Valley & Western Railroad Company
· Rio Grande Pacific
· Twin Cities & Western Railroad Company
· Willamette & Pacific Railroad
· Wheeling & Lake Erie Railway
· Wisconsin & Southern
· U.S. Army Reserves 1205th Railway Operating Battalion

Passenger Railroads
· Altamont Commuter Express
· Amtrak
· Amtrak High Speed Service
· Baltimore MTA
· Bay Area Rapid Transit (San Francisco)
· BC Transit (Vancouver)
· Calgary Transit
· Caltrain
· Capitol Corridor
· Greater Cleveland Regional Transit Authority
· Detroit People Mover
· Edmonton Transit
· GO Transit (Toronto
· Northern Indiana Commuter Transportation District
· METRA (Chicago Area Commuter Rail)
· MetroLink Light RailSystem (St. Louis)
· Metropolitan Transit Authority of Harris County (METRORail)—Houston light rail
· Miami Transit
· Montreal Commuter Rail
· Northstar Corridor Commuter Rail (Minneapolis)
· Port Authority of New York & New Jersey (PATH and JFK Airtrain)
· Portland Tri-Met
· Sacramento RTD
· Santa Clara Valley Transportation Authority
· San Francisco Municipal Railway
· Sound Transit (Seattle LRT and Sounder commuterrail)
· Utah Transit Authority (Salt Lake City LRT)
· VIARail Canada. Inc.
· Virginia Railway Express

Associations
· American Association of Railroad Superintendents
· American Passenger Rail Coalition
· Association of American Railroads
· American Public Transportation Association
· American Railroad Development Association
· American Railway Engineering & Maintenance-of-wayAssociation
· The American Short Line and Regional Railroad Association
· Association of Car Accounting and Car Service Officers (ACACSO)
· Bureau of Transportation Statistics National TransportationLibrary
· Center for Transportation Excellence
· National Association of Railway Business Women
· National Association of Railroad Passengers
· National Industrial Transportation League
· National Railroad Construction & Maintenance Association
· North American Rail Shippers Association
· Railway Association of Canada
· Railway Engineering-Maintenance Suppliers Association
· Railway Industrial Clearance Association
· Railway Supply Institute
· Railway Safety Advisory Committee
· Railway Systems Suppliers Inc.
· Railway Tie Association
· Southeastern Economic Alliance
· The National Corridors Initiative 

Railway Labor Organizations
· Brotherhood of Locomotive Engineers
· Brotherhood of Maintenance of Way Employes
· Brotherhood of Railway Signalmen
· Transportation Trades Department, AFL-CIO
· United Transportation Union 

Government & Regulatory Agencies
· Federal Railroad Administration
· Federal Transit Administration
· Federal Transit Administration, Office ofSafety and Security
· House Transportation & InfrastructureCommittee
· National Mediation Board
· National Transportation Safety Board
· Surface Transportation Board
· U.S. Department of Transportation
· U.S. DOT Office of Freight Management and Operations
· U.S. Trade and Development Agency