The American Public Transportation Association (also known as the American Public Transit Association) is a trade association for operators of public transportation systems and businesses in the public transportation industry. The organization lobbies on behalf of policies that support the use of public transportation.
The organization claims a membership of over 1,500 organizations in the public transportation industry. The APTA represents all modes of public transportation including subways, bus, paratransit, light rail, commuter rail, waterborne transit, and intercity and high-speed commuter rail. APTA claims that 90% of riders who use public transportation in the United States and Canada do so on APTA members. 
APTA provides several services to its members. Its primary service is to advocate on behalf of the public transportation industry in Washington, D.C. It pushes to increase funding for public transportation and for the adoption of pro-public transit policies by Congress and the executive branch. It is also involved in public policy research that develops pro-public transit policies. 
The APTA provides opportunities for its members to network. It hosts an annual trade show that provides a platform for manufacturers and other companies to showcase their products and services to APTA members. It maintains 135 committees, working groups, and task forces for its members to offer suggestions and network with each other. APTA also maintains a membership directory for its members to contact each other. 
APTA provides standards to improve performance of its members. It has produced safety standards which have made public transportation safer and publishes an annual fact book which provides up to date information on public transportation usage. 
APTA also provides professional development for its members. For over 20 years, Leadership APTA has graduated over 500 industry professionals. The program is designed to train the next generation of public transit professionals. APTA also provides workshops at its conference to improve the skills of mid-level managers and works with public transit leaders early in their career to improve their skills and abilities. Finally, APTA has worked to improve the process of selecting bus drivers to improve their skills and their safety. 
Paul Skoutelas is the president and CEO and has served in this capacity since 2018. He has spent his entire career in the public transit field. 
Nuria Fernandez is the chair of APTA. She is the general manager and CEO of the Santa Clara Valley Transportation Authority in Santa Clara, California. She is a former Acting Federal Transit Administrator under President Bill Clinton. 
APTA also has an executive committee and board of directors. 
According to its 2017 tax returns, APTA generated $31 million in revenue and spent $26.8 million. 
The largest expenditure was training and development. It held 10 workshops, conferences, and its annual trade show, which focused on issues that were important to its members and the public transit industry. 
APTA also spent money on federal advocacy and policy research.