Background: In Ireland the role of advanced nurse practitioner has developed significantly since 2001. This evolution is rooted in the growing recognition of the need for highly skilled nursing professionals to address complex healthcare demands and improve patient outcomes. Objective: To scope the landscape and identify the effect of advanced nurse practitioners on healthcare provision in Ireland. Design: A systematic search of eight academic databases (CINAHL, Embase, PsycINFO, Scopus, Medline and Academic Search Complete, Cochrane, Web of Science) relevant to nursing and health care were performed. Settings: Nursing care environment. Participants: Advanced nurse practitioners delivering care. Methods: A pre-defined systematic search of eight academic databases was conducted, and two reviewers screened each study against the inclusion criteria. Additional hand-searching of the reference lists (backward chaining) and citations (forward chaining) of papers that met the inclusion criteria was conducted. The methodological details of each paper were extracted and assessed for quality and rigour utilising the Mixed Methods Appraisal Tool and the Authority, Accuracy, Coverage, Objectivity, Date, Significance checklist for appraising grey literature. Data were mapped and analysed onto the six domains of advanced nurse practitioner practice, and the review was reported in line with Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Results: All papers included in this review spanned across the last 20 years. In total, 45 papers met the inclusion criteria: quantitative (n = 11), qualitative (n = 15), mixed methods (n = 4), and discussion/clinical cases (n = 15) papers. Advanced nurse practitioners in Ireland contribute substantial impacts on management and team competence, clinical-decision making, leadership and professional scholarship, professional values and conduct, communication and interpersonal competence, and knowledge and cognitive competence domains. Advanced nurse practitioners in Ireland enhance healthcare outcomes through expertise, coordination, and patient-centred approaches, emphasising their critical role in healthcare delivery and system improvements. Conclusions: We have highlighted the active role advanced nurse practitioners play in enhancing patient care, improving management and team coordination, and advancing professional scholarship. These insights have provided a foundation for future research and policy development to optimise the advanced nurse practitioner role.