The Regional Plan Association's Third Regional Plan represents the continuation of a 75 year tradition of metropolitan planning for the Tri-state metropolitan region surrounding New York City, North America's largest urban region. RPA is a non-governmental, membership organization consisting of business, civic and community leaders. RPA's first and second plans (1929 and 1968, respectively) laid out the region's basic transportation and environmental infrastructure, and led to establishment of regional authorities. The third plan's focus is on steps needed to sustain quality of life and environmental systems, and promote greater social integration and economic competitiveness in the first decades of the 21st century. Demonstration and advocacy projects completed as part of the plan have already improved the environment, community design and economic opportunity for millions of the region's residents. The process of developing the plan, and the plan's implementation strategy involves extensive collaboration among hundreds of "third sector" civic groups throughout the region. This unique collaborative process could become a model for metropolitan regions around the world.

The mission of the RPA is to improve the quality of life and the economic competitiveness of the 31-county New York-New Jersey-Connecticut region through research, planning, and advocacy.

Through this project, RPA has successfully initiated and advocated:

- permanent protection of public water supply watersheds for 14 million residents;
- protection of more than a 500,000 hectares of open space and natural areas;
- creation of new model for locally controlled regional land use regulatory systems protecting 50,000 area;
- infrastructure investments and public policies attracting or retaining one million jobs in urban centers;
- capital investments and governance reforms to rebuild subway and commuter rail services for 5 million daily riders;
- reclamation of 100 acre hectare contaminated site, as demonstration of regional brownfield recovery project.