The paper discusses the potential roles for protocols of care within critical care environments from the perspective of providing real-time support for their application. The discussion is based around a conceptual model of care in critical care environments. This model has been developed in the wider context of developing information technology systems to support clinical care in critical care environments. The conceptual model of care is a three layer model which demonstrates both the hierarchical and temporal aspects of the care delivered to patients. It is proposed that if the value of protocols of care is to be realised in critical care environments then they must be seamlessly integrated into the routine data management associated with the care of patients. In order to demonstrate this and to evaluate the utility of this concept in the clinical environment, the systems from the AIM TANIT (Telematics in Anaesthesia and Intensive Therapy) project have been used as prototype platforms. The application of the concepts developed are described in two critical care environments: the anaesthesia department and the intensive care unit. Problems in using protocols of care in intensive care units suggest that integrating these with a problem solving methodology to create an integrated care plan may be a more appropriate approach to patient management.