This book introduces readers to the basics of Advanced Practice Nursing (APN), which offers expanded clinical competence that can help improve the quality of health and care services. The book offers a range of perspectives on APN, APN models, APN education, challenges in the implementation of APN in new countries, as well as a description of the APN role, including areas of expertise. These core areas of the Caring APN model (clinical nursing practice; ethical decision-making; coaching and teaching; consultation; collaboration; case management; leadership; research and development) are described, together with the role of APN in acute care and primary healthcare service contexts. The book also explores the connection between epistemology, a three-dimensional view of knowledge (epistêmê, technê and phronesis) and a care perspective, as well as central theoretical aspects of nursing, e.g. health, holism and ethics/ethos. All research should be grounded in theoretical perspectives, and here we highlight the value of a caring and person-centered philosophy in advanced practice nursing. Through its specific focus on the central, generic theoretical features of nursing science that deepen the role of APN and the scope of practice and APN research and education, the content presented here will help any researcher, teacher or student understand the importance of epistemological issues for research, education and clinical practice in this field. Moreover, it can be used when designing Master's programs in Advanced Practice Nursing, making the book a valuable resource for the international nursing community.