Recent implementation of modern armoured fighting vehicles in Swedish army forces has been substantial. In consequence, changes in the knowledge area of battlefield emergency care have been so large that a new professional competence is demanded. The aim of this study was to explore and describe how nurses perceive battlefield emergency care. A qualitative design was used comprising in-depth research interviews with 11 male registered nurses who all had been trained as company nurses in the Armed Forces. Three major themes were described; Unpredictable and invisible, a contextual leadership and assimilation acts. From the first major theme, the characteristic of battlefield emergency care is that it is unpredictable and invisible with the subthemes: menacing, unknown, challenging and complicated. From the next major theme, that a contextual leadership is important to have, with the subthemes: field manners, responsibility capacity and capacity to determine. The third major theme assimilation acts with the subthemes: experience from combat casualty care, education, working experience and by utilizing research findings. If we are to be able to offer patients individualised and qualitatively good professional care, emergency care must be conducted on the basis of scientific and well-tried experience.