U.S. science and engineering organizations are voicing concerns about reductions in federal science advisers to President Donald J. Trump. In a letter, the American Chemical Society, the American Association for the Advancement of Science, and 12 other scientific societies urge Trump and his Administration to protect the integrity of scientific guidance in governing. “Federal advisory committees are an essential means for the government to have access to expert advice and ideas that reflect a broad spectrum of scientific disciplines,” the letter says. The group cautions against selecting, removing, or replacing science advisors in a manner that would compromise scientific integrity or introduce conflicts of interest. ACS spokesperson Glenn S. Ruskin says, “ACS appreciates the right of each Administration to set its own priorities across federal agencies, but the society does not believe any administration has the right to ignore or alter scientific data, including the availability and preservation of scientific research on critical topics such as climate change and chemical safety.” ACS publishes C&EN. The letter comes after federal agencies removed climate change data from their websites and EPA began to winnow a group of external scientific advisers.