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Union of Concerned Scientists logo

Union of Concerned Scientists

IRS-recognized 501(c)(3) international and foreign affairs nonprofit based in Cambridge, MA.

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57

About

The Union of Concerned Scientists (UCS) is a national nonprofit based in Cambridge, Massachusetts, that puts rigorous, independent science into action, developing solutions and advocating for a healthy, safe, and just future. Founded by scientists and students at the Massachusetts Institute of Technology, UCS combines technical analysis with advocacy and grassroots mobilization to influence public policy.

Mission

UCS puts rigorous, independent science to work, analyzing problems, exposing scientific misinformation, advocating for policy changes, and mobilizing supporters to drive tangible results. The organization is committed to the approach of its founders: sharing information, pursuing truth, and letting evidence guide conclusions.

What they do

  • Climate: advocating for emissions reductions and climate action.
  • Clean energy, food, and transportation: advancing sustainable systems for how the country produces energy and food and moves people and goods.
  • Nuclear weapons: working to reduce the threat of nuclear weapons.
  • Equity: working to advance racial and economic equity in these policy areas.
  • Scientific integrity: countering scientific misinformation and defending the role of science in public policy.

History

The Union of Concerned Scientists was founded in 1969 by scientists and students at the Massachusetts Institute of Technology, including physicists Henry Kendall and Kurt Gottfried, at a time when the Vietnam War was at its height and Cleveland's polluted Cuyahoga River had caught fire. The founders drafted a statement calling for scientific research to be redirected away from military applications and toward pressing environmental and social problems.

Scale and impact

According to the organization, UCS has nearly 250 staff scientists, analysts, policy experts, organizers, and communicators; a Science Network of 23,000 experts; more than 109,000 committed donors; about 500,000 supporters mobilized for advocacy; and partnerships with over 1,500 local and national organizations.

Financials

UCS states that 88 percent of its funds go to programs and that it is funded exclusively by individuals and independent foundations, accepting no corporate or government grants. Per its Form 990 data on ProPublica Nonprofit Explorer for the fiscal year ending September 2025, UCS reported total revenue of $55.5 million (91.6 percent from contributions), total expenses of $49.8 million, and net assets of $71.6 million. UCS is a 501(c)(3) organization, EIN 04-2535767, tax-exempt since 1974.

Sources

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