World Wildlife Fund

The iconic panda logo has made the WWF instantly recognizable to many people around the world. With 5 million members internationally and over 1.2 million in the States, this 45-year-old wildlife defense organization is going strong. Strongly promoting an emphasis on science, the WWF works to preserve nature and its creatures. From the organization's website: "We are committed to reversing the degradation of our planet's natural environment and to building a future in which human needs are met in harmony with nature. We recognize the critical relevance of human numbers, poverty and consumption patternsto meeting these goals".

Earth First!

Famously unapologetic, Earth First! came to national prominence in the 1990s. Earth First! is a little different. There's no slick website. There's no bureacracy. There are no members. They welcome any and all. The entire premise of this biocentric "movement" as it calls itself is to foster direct action. Founded in 1979 out of disgust at corporate environmentalism and "namby pamby" green action, Earth First!ers have famously gotten involved in green issues directly, sometimes breaking the law. Calling itself a priority, not an organization, the website explains: "Earth First! has survived attacks by moderates, would-be leaders and the agents of the system, remaining the most diverse, passionate, committed, and uncompromising group of environmental activists. Our direct actions in defense of the last wild places only seem radical compared toan entire paradigm of denial and control, where the individual is convinced they are powerless, and the organizations set up to protect the wilderness continue to bargain it away".

Greenpeace

Greenpeace began in 1971 when a group of activists put themselves directly in harm's way in order to protest nuclear testing off the coast of Alaska. Believing that concerted action from ordinary people is the best way – according to their signature quote from Margaret Mead, the only way – the organization has helped to stop whaling, nuclear testing, as well as leading efforts to protect Antarctica. Over 2.5 million members worldwide.