Aims: The comprehensive review sought to examine the impact of Critical Care Nurse Practitioner models, roles, activities and outcomes. Method: The Medical Literature Analyses and Retrieval (MEDLINE), The Cumulative Index of Nursing and Allied Health Literature (CINAHL); PubMED; PROQUEST; ScienceDirect; and the Cochrane database were accessed for the review. Alternative search engines were also included. The search was conducted with the key words: critical care, intensive care, acute, adult, paediatric, trauma, disease management programs, disease management, case management, neonatal, cardiology, neurological, retrieval, transfer and combined with Nurse Practitioner. From the identified 1048 articles 47 studies were considered relevant. Results: Internationally, Critical Care Nurse Practitioners were located in all intensive care areas and services including post intensive care discharge follow-up, intensive care patient retrieval and transfers and follow-up outpatient services. The role focussed on direct patient management, assessment, diagnosis, monitoring and procedural activities. Critical Care Nurse Practitioners improved patient flow and clinical outcomes by reducing patient complication, morbidity and mortality rates. Studies also demonstrated positive financial outcomes with reduced intensive care unit length of stay, hospital length of stay and (re)admission rates. Conclusions: Internationally, Critical Care Nurse Practitioners are demonstrating substantial positive patient, service and nursing outcomes. Critical Care Nurse Practitioner models were cost effective, appropriate and efficient in the delivery of critical care services.