Triangle Greenways Council
- Promotes and protects corridors of natural land in the area. Features trail maps, newsletter, meeting minutes, membership information. Based in Raleigh.
- http://www.trianglegreenways.org

Triangle Clean Cities Coalition
- A voluntary group of public and private entities working to increase the use of alternative fuel vehicles to improve air quality and reduce dependence on foreign oil.
- http://www.trianglecleancities.org/

Eno River Association
- Non-profit organization devoted to protecting the Eno River from development and pollution. Calendar of events, wildflower photos, maps, and newsletters.
- http://www.enoriver.org/

Triangle Land Conservancy
- Nonprofit corporation whose mission is to create a regional network of open space and natural areas in the six county Triangle region of North Carolina (Chatham, Durham, Johnston, Lee, Orange and Wake counties).
- http://www.tlc-nc.org/

RTI International
- Conducts contract research in medicine, pharmaceuticals, public health, advanced technologies, environmental protection, and public policies.
- http://www.rti.org/