Tularaemia is a bacterial zoonotic disease of the northern hemisphere. The bacterium (Francisella tularensis) is highly virulent for humans and a range of animals such as rodents, hares and rabbits. Humans can infect themselves by direct contact with infected animals, by arthropod bites, by ingestion of contaminated water or food, or by inhalation of infective aerosols. There is no human-to-human transmission. In addition to its natural occurrence, F. tularensis evokes great concern as a potential bioterrorism agent. F. tularensis subspecies tularensis is one of the most infectious pathogens known in human medicine. In order to avoid laboratory-associated infection, safety measures are needed and consequently, clinical laboratories do not generally accept specimens for culture. However, since clinical management of cases depends on early recognition, there is an urgent need for diagnostic services. This first edition of WHO Guidelines on tularaemia provides background information on the disease, describes the current best practices for its diagnosis and treatments in humans, suggests measures to be taken in case of epidemics and provides guidance on how to handle F. tularensis in the laboratory. The target audience includes clinicians, laboratory personnel, public health workers, veterinarians, and any other person with an interest in zoonoses.