In the last 2 decades, successive outbreaks caused by new, newly recognised and resurgent pathogens, and the risk that high-consequence pathogens might be used as bioterrorism agents amply demonstrated the need to enhance capacity in clinical and public health management of highly infectious diseases. In this article we review these recent and current threats to public health, whether naturally occurring or caused by accidental or intentional release. Moreover, we discuss some components of hospital preparedness for, and response to, infectious disease of the emergencies in developed countries. The issues of clinical awareness and education, initial investigation and management, surge capacity, communication, and caring for staff and others affected by the emergency are discussed. We also emphasise the importance of improving the everyday practice of infection control by healthcare professionals.