Aim: Advanced Practice Nurses are expected to provide lifesaving care to patients with complex acute illnesses in emergency and critical care settings. However, little is known about their competencies and barriers to practice in emergency and critical care settings. This review investigated these nurses' competencies to practice., Methods: A scoping review was conducted in accordance with Arksey and O'Malley's framework. Extensive research searches were conducted using seven electronic databases: MEDLINE, CINAHL, Scopus, Web of Science, Ichushi Web, Mednar and GreyNet International. Definitions and explanations of Advanced Practice Nurse competencies were categorized into elements and grouped according to similarity., Results: The database searches identified 2,483 studies, and data were extracted for 23 studies. Analysed studies were published between 2000 and 2021 and conducted in eight countries. Seven competencies were identified: performing advanced practice nursing, acute patient care, diagnostic assessment, interdisciplinary collaboration and consultation, leadership and system management, documenting patient care and supporting patient and family decision-making., Conclusion: This review identified competencies unique to Advanced Practice Nurses in emergency and critical care settings. Further research is required to facilitate understanding of the crucial roles of advanced care nurses among healthcare providers., (© 2023 John Wiley & Sons Australia, Ltd.)