Background: The task of improving patient safety has emerged in Ireland and internationally as a challenge for health services. Nurses have been identified as key players in patient safety due to the nature of their work. Aims: The overall aim of this study is to identify organisational and nursing factors in acute general hospitals which enable the delivery of safe patient care. Methods: The study was conducted in selected medical and surgical wards in 30 acute hospitals in Ireland. It sought to clarify organisational, ward and nurse factors which impact on nurse and patient reported patient safety outcomes through both regression analysis and multilevel modelling. Three surveys were conducted and linked together within the study: an organisational survey (n=30), a nurse survey (n=1,406) and a patient survey (n=285). Results: The organisational approaches to patient safety, taken by acute hospitals in Ireland, are presented. Nurses‟ perceptions of their work environment, of their work and workload, and of aspects of safety in their workplaces are included. Patient satisfaction data are reported, specifically that which relates to their perceptions of medication safety. Factors including the proportion of nurses on the ward with degrees, the experience level of the nursing staff, ward confidence in management, and the nurse work environment are shown to impact on nurse-reported patient safety outcomes. A link between staff ratios (registered nurse to health care assistants, and staff nurses to non-consultant hospital doctors) and patient satisfaction with medication safety is also revealed. Conclusion: Factors identified in this research have the potential to enhance patient safety in Irish hospitals. They have been shown to be associated with safer patient care, and higher rates of adverse event reporting by nurses, demonstrating a greater staff focus on the systems approach to safety.