The Population Institute is a charity based in Washington, D.C., United States.
Global Population Speak Out (GPSO) is its special project. Founded by John Feeney, PhD, an ecological writer and activist based in Boulder, Colorado, United States, GPSO is designed to boost public discussion of human population as a key factor in the struggle for sustainable living on earth.
The project has three stages. First, a pledge letter explaining GPSO is endorsed by a group of high-profile scientists, activists and celebrities. Over the years, endorsers have included scientists such as Paul R. Ehrlich, and Dennis Meadows. The letter is distributed to people interested in human population dynamics, urging them to speak out publicly during the month of February about the growing human population. Scientists, representatives of environmental NGO’s, science writers and activists, along with ordinary concerned citizens are targeted. Finally, the recruits are asked to report their project activities back to the GPSO coordinator, who posts them on the GPSO website.