During an emergency, response has to be immediate. Deliberation time is limited, even nonexistent. But professionals are responsible for their decisions and their actions. The complexity of decision-making during an emergency is an under-researched topic in bioethics. To contribute to this topic, this article focuses on decision-making by firefighter first responders. It presents empirical data from focus groups with firefighters who are first responders for the Service de Sécurité Incendie de la Ville de Montréal. First, this article describes the way that firefighters understand decision-making during an emergency. Second, an empirical approach is shown to be necessary for bioethics researchers who venture to do research in fire departments: this empirical approach reveals firefighter’s ethical challenges and how they can be neutralised.