Employees are often considered a vulnerable research population due to concerns about consent and confidentiality, but there is insufficient guidance regarding their ethical inclusion in research . In the context of Covid-19, frontline health care workers comprise a particularly relevant research population in light of their risks of viral exposure and psychological strain, among other factors . They may therefore be targeted for research conducted at their place of employment and benefit from participating in such research . Beyond Covid-19, there are other circumstances in which health care workers may be considered for inclusion in research conducted by or with the involvement of their colleagues and employers . As investigators, sponsors, institutional review boards, and others assess the ethical permissibility of these scenarios, as well as relevant protections, we recommend systematic consideration of social and scientific value, validity, fairness, risks and benefits, voluntary consent, respect, and independent review . There is often good reason to specifically target health care workers for inclusion in Covid-19 research (beyond convenience), and they should not be excluded from research offering the prospect of direct benefit . However, additional safeguards may be necessary in employer-based research to avoid scientific bias, promote voluntariness, and solicit stakeholder input . Research personnel should be permitted to enroll in their own Covid-19 studies only when participation offers them the prospect of unique benefits.