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Science in service of people and the planet.
The Union of Concerned Scientists is a member-supported nonprofit that’s fighting for a safer and healthier world.
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Colliding Crises
Across the US, the housing crisis and climate change-fueled extreme heat are increasingly colliding.
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2025 Annual Report
Science won't be silenced.
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Scientists Respond to the Trump Administration
Our experts and analysts weigh in on the latest developments from the White House.
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UCS: What We Do
Breathtaking imagery from photographer Daniel Beltrá showcases the range of issues that UCS works on.
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New CA Laws Reflect Years of UCS Work
Three new UCS-supported laws will save Golden State ratepayers money and increase the amount of clean energy flowing to California’s electric grid, paying off years of analysis and advocacy from UCS Western States staff.