Adana Llanos knows it takes years to build trust, but only seconds to break it. That's especially true when doing research with people of color: Historical abuses and pervasive racism in health care systems make many hesitant to participate in studies today. The Columbia University epidemiologist has spent nearly 2 decades forging relationships with community partners, laying groundwork that enables her to study nuanced issues such as how neighborhood environments contribute to breast cancer severity in racially diverse populations. "This isn't just [research] that I decided to do last year," she says. But that hard-won trust may now be at risk. On 14 March, the National Institutes of Health (NIH) abruptly terminated two of Llanos's three grants. One was for a study of how societal factors affect whether a woman receives the best care for cervical cancer and present barriers to treatment; it had enrolled about 200 of its intended 960 participants. Llanos is looking for alternative funding to restart recruitment, and to compensate the members of the community who served as advisers for the work so far. But even if the NIH money were restored, she says, the researchers could miss critical time points to follow up with the women already enrolled. Her other project, a breast cancer study, is also on hold.