Scholars of nursing practices have claimed practical knowledge is source of knowledge in its own right, nevertheless we know little about this knowledge associated with day-to-day practice. The purpose of this study is to describe knowledge that the more experienced nurses the in ICU make use of and discover the components of care it includes. Understanding this knowledge can contribute to improving the working practices of nurses with less experience. Methods: We used a phenomenologic and hermeneutic approach to conduct a qualitative study. Open in-depth dialogue interviews were conducted with 13 experienced ICU nurses selected by intentional sampling. Data was compiled on significant stories of their practice. The data analysis enabled units of meaning to be categorised and grouped into topics regarding everyday practical knowledge. Results: Knowledge related to everyday practice was evaluated and grouped into seven topics corresponding to how the ICU nurses understand their patient care: 1) Connecting with, calming and situating patients who cannot communicate; 2) Situating and providing relief to patients in transitions of mechanical respiration and non-invasive ventilation; 3) Providing reassurance and guaranteeing the safety of immobilised patients; 4) The 'connection' with patients in comas; 5) Taking care of the body; 6) The transition from saving life to palliative care; and 7) How to protect and defend the patient from errors. The components of caretaking that guarantee success include: the calm, care and affection with which they do things; the time devoted to understanding, situating and comforting patients and families; and the commitment they take on with new staff and doctors for the benefit of the patient. Conclusions: These results show that stories of experiences describe a contextual practical knowledge that the more experienced nurses develop as a natural and spontaneous response. In critical patients the application of everyday practical knowledge greatly influences their well-being. In those cases in which the nurses describe how they have protected the patients from error, this practical knowledge can mean the difference between life and death. The study highlights the need to manage practical knowledge and undertake further research. The study is useful in keeping clinical practice up-to-date.