The US government’s growing concern over potential foreign influence on research and researchers is intended to protect commercial and national interests. But the varying security requirements often leave researchers burdened, confused, and intimidated. Many scientists worry that they will lose collaborations—especially with colleagues in China—and that the clampdown will erode US scientific leadership. For more on the evolving research-security scene, see the story on page 16 . (Cover image adapted from iStock.com/lucky sun.)