• This article reports on observation of 18 nurses in urban and rural based critical care settings.<br><br>• The purpose of the study was to observe and describe the decision-making activities of critical care nurses within natural clinical settings.<br><br>• During the 2-hour observation, the researcher dictated a detailed commentary on to audio-tape of each nurse's actions. Tapes were transcribed and subjected to content analysis.<br><br>• Findings indicated three main categories of decisions. Decision frequencies were linked to nurses' critical care experience, appointment level, and location, as well as nursing shifts.<br><br>• The findings are discussed in relation to previous empirical evidence and the implications for practice.<br><br>• The author concludes that future research should be directed towards measuring the contextual influences on nurses' decision-making on the outcome of patient care.<br>