Science is being attacked from many angles. In my last post, I wrote about what that means for early-career scientists and experts, and how funding cuts, disappearing programs, and fewer opportunities are already affecting the next generation of scientific talent. Not knowing whether your research will be funded or whether a position will exist is difficult enough. But for many international scientists and students, there’s another layer of uncertainty: wondering whether you’ll be able to stay in the country long enough to build your career.
International scientists have long been an essential part of the US scientific enterprise. Scientists and technical experts from around the world come here to study, conduct research, collaborate, and, in many cases, stay and join the US workforce. That exchange has helped make American science what it is today. Cultivating diversity in American science isn’t just about adding people to labs and institutions: scientists from different backgrounds contribute their varied experiences and ways of thinking to expand perspectives and provide new possibilities for problem-solving.
International scientists are a significant part of the US scientific workforce. In 2024, temporary visa holders earned nearly 40 percent of all science and engineering doctorates awarded by US universities. In fields like engineering, mathematics, and computer science, they earned more than half. Nearly half of US science and engineering workers with doctoral degrees were born outside the United States.
But more recently, changes to US immigration policy have created uncertainty for international students and researchers. Expanded immigration screening, travel restrictions, visa delays, and changing rules around student and skilled-worker visas are forcing some scientists to make decisions that have little to do with the science they came here to do. For example: Do I travel home to see my family if I’m not sure I’ll be able to return? Do I accept a position in the United States if my visa could delay my start date? Do I build a career here at all?
When uncertainty changes the plan
For many international scientists, these policies are already changing how they think about their careers.
One PhD student from India came to the United States because she believed there were opportunities for researchers that she couldn’t find anywhere else. She planned to stay after finishing her degree, and already had a postdoctoral fellowship lined up. But while she was back in India, new requirements for renewing her visa (including making her social media accounts public for government review) kept her away from her lab for two months during a critical point in finishing her doctoral program.
Her visa was eventually approved. But by then, she had already changed her mind.
Instead of staying for her postdoc, she decided to return to India for a job in biotechnology. As she told STAT News, the process was simply no longer worth the uncertainty. And with scientific opportunities growing elsewhere, staying in the United States was no longer the obvious choice.
She isn’t the only scientist reconsidering her plans. In a 2026 survey of nearly 1,000 NIH-supported researchers, 14 percent said changes in immigration policy had caused scientists, students, or postdocs to turn down positions in their labs. Researchers also reported receiving fewer applications from international scientists and seeing trainees consider leaving the United States altogether.
But leaving isn’t the only way this uncertainty is showing up.
A Vietnamese PhD student studying in Louisiana canceled a trip to visit research collaborators in Europe because he was afraid he might not be able to return to the United States. Although he was legally studying here, his visa had expired, and traveling would have required him to apply for a new one before returning. Rather than take the risk, he stayed. He has also made plans to earn a master’s degree along the way so that if something interrupts his ability to finish his PhD, he’ll at least leave with a completed degree.
Scientists are reconsidering where to build their careers. They’re avoiding international travel and collaborations. They’re making backup plans in case they can’t finish their degrees. Some labs are becoming more hesitant to offer positions to researchers who need visas because they can’t risk having positions sit vacant during long processing delays.
Institutions are changing their behavior, too; part of the ripple effect. When institutions are worried about running afoul of changing immigration rules, they may become more cautious too—and students ultimately feel the consequences.
This summer, US Immigration and Customs Enforcement (ICE) issued new guidance narrowing when universities can authorize Curricular Practical Training (CPT), which allows F-1 international students to participate in internships and other practical training related to their studies. The guidance warned that institutions could risk losing their ability to enroll international students if they fail to comply. In response, universities including UCLA and UC Berkeley paused or restricted some of their applications while they reviewed the new requirements.
There are signs that more early-career scientists are looking elsewhere. Among international students who earned US physics PhDs in 2025, 29 percent left the United States, a 30-year high. Immigration isn’t the only factor shaping those decisions: funding, research opportunities, and other conditions matter, too. But taken alongside reports of declining applications, rejected positions, and growing visa uncertainty, the trend is worth paying attention to.
What does this mean for US scientific progress?
International scientists aren’t just people who happen to study or work here. They are our classmates, colleagues, mentors, lab partners, and collaborators. Foreign-born workers make up nearly 30 percent of the college-educated US science and engineering workforce. Science itself has become increasingly international, with US researchers contributing to nearly 240,000 papers coauthored with researchers in other countries in 2024 alone.
Some of the biggest problems we’re trying to solve don’t care about borders: e.g., climate change; stopping the spread of infectious diseases. We’re better equipped to take on these problems when the people trying to solve them bring different expertise, experiences, and perspectives to the table.
There are economic consequences, too. Research has found that immigrant inventors make outsized contributions to US patents and innovation, including through the ideas and knowledge they share with their U.S.-born collaborators.
So what happens if fewer young scientists see the United States as a place where they can build their future?
The concern isn’t that scientific talent will suddenly disappear. Scientific talent is global. Researchers who decide not to come here may build successful careers in India, Germany, Canada, Nigeria, China, and elsewhere. Other countries are investing heavily in their own scientific enterprises, and the United States doesn’t (and absolutely shouldn’t) have a monopoly on good ideas. A scientist choosing to build a career somewhere other than the United States isn’t a loss for science. But the United States has benefited tremendously from being a place where scientists from around the world wanted to come, exchange ideas, collaborate, and sometimes stay. We shouldn’t assume that will always be the case.
If we make it increasingly difficult or unpredictable for people to comfortably study here, work here, travel, collaborate, or simply plan their lives, people have other options. And honestly, can we blame them for considering those options?
So: what can we do?
In my last post, I wrote about finding your lane in advocacy. I’ll say it again here because I think it’s really important. If you have more security (whether because of your citizenship, immigration status, position, or institution) you may also have more room to speak up when your colleagues can’t. Ask your university, professional society, or employer what it’s doing to support international students and researchers. Pay attention when policies affecting your international colleagues change, and don’t leave it entirely to the people most affected to raise the alarm.
If you work at a university or research institution, push for clear information and meaningful support for international students and staff. That can mean access to immigration resources, flexibility when visa delays interrupt research or travel, and making sure institutional responses to changing federal policies don’t create unnecessary barriers of their own.
And keep building relationships across borders. Collaborate. Share opportunities. Invite international colleagues into the room. Support early-career scientists wherever they’re building their careers.
Most importantly, listen to the international scientists around you. Ask what they need! Their experiences aren’t all the same, and we shouldn’t assume we already know the answer.
I also said in my last post that there isn’t one way to advocate for science. That applies here, too. Maybe your lane is speaking up within your institution. Maybe it’s contacting decisionmakers. Maybe it’s making sure your international colleagues know what resources and support are available at your institution, and advocating for better ones when they’re not enough. Maybe it’s simply paying attention and refusing to let these changes happen quietly.
Science has always depended on people sharing ideas across institutions, disciplines, communities, and borders.
Protecting the people who make that exchange possible is part of protecting science, too.