By virtue of their professional ethics as healers and because of their specialized technical knowledge and clinical experience in assessing and reacting to real and potential emergencies, physicians have an obligation to offer an unsolicited medical opinion when the following conditions are met: (1) physicians assess a high probability of potentially serious disease in a stranger because of information presented to them, either in the form of a communication or physical signs; (2) physicians judge this information to be latent (not readily interpretable as potentially dangerous by the stranger) and likely to remain latent prior to the onset of symptoms; (3) the physicians possess the medical knowledge appropriate to the professional interpretation of this information. Although not a morally risk-free endeavor (invasion of privacy and the potential creation of a ‘sick role’ whether or not the diagnosis is correct), offering an unsolicited medical opinion under the above conditions can prevent suffering and save lives in unsuspecting strangers.