A case study is a research methodology commonly used in social and life sciences, characterized by an intensive, systematic investigation of a single individual, group, community, or unit. It aims to generalize findings over several units and examines complex phenomena in their natural settings to enhance understanding. Case studies can be single-case or multiple-case, with the latter involving the evaluation of several similar cases to gain a more comprehensive understanding. The method involves defining the case, conducting a literature review, collecting qualitative and/or quantitative data, and analyzing it to identify themes and assertions about the cases as a whole. Benefits include deeper insights and stronger evidence, while limitations include data organization challenges and the risk of deviating from the research focus. Examples of case studies include exploring nurses' pediatric pain management practices and the quality of care for complex patients at Nurse Practitioner-Led Clinics (NPLCs). These studies highlight the holistic nature of nursing practice and contribute to improved patient care.A case study is a research methodology commonly used in social and life sciences, characterized by an intensive, systematic investigation of a single individual, group, community, or unit. It aims to generalize findings over several units and examines complex phenomena in their natural settings to enhance understanding. Case studies can be single-case or multiple-case, with the latter involving the evaluation of several similar cases to gain a more comprehensive understanding. The method involves defining the case, conducting a literature review, collecting qualitative and/or quantitative data, and analyzing it to identify themes and assertions about the cases as a whole. Benefits include deeper insights and stronger evidence, while limitations include data organization challenges and the risk of deviating from the research focus. Examples of case studies include exploring nurses' pediatric pain management practices and the quality of care for complex patients at Nurse Practitioner-Led Clinics (NPLCs). These studies highlight the holistic nature of nursing practice and contribute to improved patient care.