Abstract Background Physician impairment is defined by the presence of a physical, mental, or substance-related disorder that interferes with the ability to practice medicine competently and safely. The seeds of impairment may be sown early in adulthood, and medical students experience health issues that may receive insufficient attention in the context of a rigorous training period. Few empirical studies have examined the attitudes of medical students toward recognizing and acting upon signs of potentially impairing illnesses in peers. Method Medical students at 9 medical schools were invited to participate in a written survey exploring personal health care issues during training. As part of this larger project, students were asked to imagine their response in 3 situations to a medical student who is discovered to have serious symptoms and potential impairment secondary to mental illness, substance abuse, or diabetes. Results Responses were gathered from 955 students (52% overall response rate). For all of the vignettes, “tell no one but encourage him/her to seek professional help” was the most prevalent reaction (45%, 53%, and 49%, respectively) as opposed to seek advice (37%, 35%, and 42%) and notify the Dean's office (18%, 12%, and 9%). Willingness to report varied by school, and women were somewhat less likely to formally report medical student illness. Conclusion This study suggests that medical students attach great importance to preserving the confidentiality of fellow medical students who may experience even very severe symptoms. This pattern may have important implications for the early recognition and treatment of potentially impairing disorders. Greater attention to these issues may help assure the health of early career physicians as well as the many patients whose safety and well-being are entrusted to their care.