Clinical decisions are often informed by the experience and expertise of colleagues but this may not be enough to ensure safe, effective practice. Two decisions made about the care of an infant in a special care baby unit are analysed to demonstrate the importance of basing decisions, not just on experience, but also on published research as well as protocols, guidelines and textbooks that are informed by research. A seven-stage model of decision making is used as a framework to support the analysis, which identifies the importance of cognitive skills such as generating and testing hypotheses in the process of making effective decisions.