This study focused on work-related stress among nurses working with critically ill patients. The aim of the study was to examine the effects of work-related stress with regard to patient safety. The study uses a qualitative design based on focus group interviews with nurses who work with acute, critically ill patients in hospitals. Two regional hospitals were chosen. Inclusion criteria for the focus group panels included the following: nurses with advanced training in anesthesiology, intensive care, or operating-room nursing. Twenty-three nurses were chosen and they were divided into four groups. This study shows that a demanding work environment together with minimal control and social support from colleagues results in increased stress that can often have an effect on patient safety.