The aim of this study was to describe nurses' conceptions of decision making with regard to life-sustaining treatment for dialysis patients. Semistructured interviews were conducted with 13 nurses caring for such patients at three hospitals. The interview material was subjected to qualitative content analysis. The nurses saw decision making as being characterized by uncertainty and by lack of communication and collaboration among all concerned. They described different ways of handling decision making, as well as insufficiency of physician-nurse collaboration, lack of confidence in physicians, hindrances to patient participation, and ambivalence about the role of patients' next of kin. Future research should test models for facilitating communication and decision making so that decisions will emerge from collaboration of all concerned. Nurses' role in decision making also needs to be discussed.