Since its inception, intensive care units are designed as restricted spaces because of the risk posed by the critical condition of the patients and the complexity of their health status, but with the elapse of time, the experiences of health professionals and the incorporation of different theories of nursing in the care of patients, the needs of family and patients have become increasingly apparent , and this has prompted the study of family involvement in meeting those needs and in the patient recovery. For this reason, it is necessary that family involvement becomes a priority and reality in intensive care units. This article shows the importance of family involvement and offers the possibility to operationalize it in critical patient care through the application of a theory such as Rosemarie Parse´s, whose theoretical foundation is correlated with the process of family involvement and can articulate the disciplinary elements in professional practice. For this, this article, which is the result of a literature review, is derived from international guidelines for family involvement and integrates with the models of a macro theory called man living-health.