Colorado Open Lands
- A land conservation organization dedicated to preserve open lands through private and public partnerships, innovative land conservation techniques, and strategic leadership.
- http://www.coloradoopenlands.org

Climate of Colorado
- Narrative written by the State Climatologists and published by the National Climatic Data Center.
- http://www.wrcc.dri.edu/narratives/COLORADO.htm

Colorado Natural Areas Program
- Dedicated to preserving and protecting natural resources. Includes information regarding native plant communities, geologic formations, paleontological localities, and habitat for rare plants and animals.
- http://parks.state.co.us/NaturalResources/CNAP/

Colorado Renewable Energy Society (CRES)
- Increases the awareness of the economic and environmental benefits of solar, wind, biomass, geothermal, and energy efficiency technologies.
- http://www.cres-energy.org

A-LP Central
- Articles and general information about the defense of the Animas and LaPlata rivers, especially the fight against the proposed dam project.
- http://www.alpcentral.com/

Colorado Wildlife Viewing
- Information from the Colorado Division of Wildlife. [Javascript required]
- http://wildlife.state.co.us/Viewing/

Northern Colorado Renewable Energy Society
- Promotes the social, economic, and environmental benefits of solar, wind, biomass, geothermal, and energy efficiency technologies. Links, upcoming events, and board directors.
- http://www.ncres.org

Colorado Wildlife Federation
- To promote the conservation, sound management, and sustainable use of Colorado's wildlife and habitat through education and advocacy.
- http://www.coloradowildlife.org/

Colorado Guide: Wildlife Watch
- Viewing and natural history guide to wildlife of the Rockies. Includes photographic tips and techniques.
- http://www.coloradoguide.com/wildlife/

Coalition for the Upper South Platte
- Dedicated to protecting the water quality and ecological health of the Upper South Platte watershed, and managing the Hayman Recovery Assistance Center. Also designed to collect information for fire victims needing assistance.
- http://www.uppersouthplatte.net/

Colorado Alliance for Bioengineering
- A consortium of local universities committed to producing a high quality workforce and enhancing bioengineering research and development in the state of Colorado. Highlighting fellowship and internship opportunities.
- http://www.coloradobioengineering.org/

Colorado Foundation for Water Education
- An independent non-profit organization working to promote better understanding of Colorado's water resources and issues by providing balanced and accurate information and education.
- http://www.cfwe.org/

East of Huajotalla Citizens Alliance
- Educational and activist information on Coal Bed Methane Development in the Raton Basin of southern Colorado. Includes news and articles, calendar of events, and statistics.
- http://ehcitizens.org/cbmgas/

The Trust for Land Restoration
- A non-profit land trust dedicated to understanding and managing environmental liability. Includes a legal guide and current proposals, policies, board of directors, and annual report.
- http://www.restorationtrust.org/

The Nature Conservancy of Colorado
- A nonprofit environmental conservation organization dedicated to preserving biodiversity by protecting habitat for species of plants, animals, and natural communities.
- http://nature.org/wherewework/northamerica/states/colorado/

Colorado Water Knowledge
- Contains information about water resources in Colorado. Topics include water quality, major river basins, aquatic organisms, wetlands, conservation, and water law.
- http://waterknowledge.colostate.edu/

Colorado Nature Series
- Articles about plants, animals, ecology, geology, and paleontology. Also includes discussions regarding the wildfires and drought conditions.
- http://www.suite101.com/welcome.cfm/colorado_nature_series

North Fork River Improvement Association
- Non-profit organization working to improve and restore the North Fork of the Gunnison River and the related ecosystems. Features current projects, partners, events, and newsletter.
- http://www.nfria.paonia.com

BASIN - The Boulder Area Sustainability Information Network
- Extensive source of information, including real-time monitoring data, on water resources and other environmental conditions in and around Boulder, Colorado.
- http://bcn.boulder.co.us/basin

Colorado State University Cooperative Extension
- Information for consumers about crops, farm management, food and nutrition, gardening, insects, livestock, resources and youth development across the state.
- http://www.ext.colostate.edu

Western Colorado Congress
- Grassroots, democratic group organizing people to increase their power on issues of environmental stewardship, sustainable communities and economic justice.
- http://www.wccongress.org

Colorado Environmental Coalition
- The citizens' voice for Colorado's environment since 1965.
- http://www.ourcolorado.org

Colorado Wild
- Coalition working to halt environmentally damaging ski area expansions, logging, and out-of-control motorized recreation to protect wildlife in the forests of Colorado.
- http://www.coloradowild.org/index.html

Dolores Water Conservancy District
- Located in the Dolores and San Juan river basins in southwestern Colorado, is developing water from the Dolores River for:irrigation, municipal and industrial users, recreation, fish and wildlife, hydroelectric power.
- http://www.doloreswater.com

Sierra Club Rocky Mountain Chapter
- Colorado chapter of the environmentalist organization.
- http://www.rmc.sierraclub.org/