OBJECTIVE Nurses are increasingly using computerised decision support systems (CDSS) to support their practice. Previous studies have highlighted the importance organisational factors have on the successful implementation of new technologies in healthcare. However, it is unclear how the organisations where nurses work either facilitate or inhibit the successful use of CDSS. The aim of this paper is to explore what nurses and NHS (National Health Service) managers working in NHS organisations in England perceive as the organisational features facilitating the introduction and successful use of CDSS. METHODS A study of four case sites where nurses were using CDSS. Data included 124 observations of nurse/patient consultations, 36 patient interviews, 55 nurse interviews and 18 interviews with clinical unit or NHS managers. The majority of the data were qualitative and analysed using thematic content analysis. FINDINGS There were a number of drivers for the introduction of CDSS, including instigation from individual clinicians and initiatives at policy level. A key element for the successful introduction of technology such as CDSS was clinician engagement. However, also seen as important for successfully implementation of an IT system are other factors such as the need for adequate resources, characteristics of the system itself and adequate training. Other key issues are a supportive environment and the desire to improve continually the quality of patient services. CONCLUSIONS For nurses to use CDSS successfully, engagement by clinicians in the procurement and implementation of systems is useful. However, the data collected in this study suggest this is not necessary for successful implementation; nurses may still successfully introduce and use a CDSS if they perceive it to have benefits to their practice.