Written by a Clinical Nurse Specialist for Clinical Nurse Specialists, this text explores the expanding roles and responsibilities of the CNS—from core competencies and theoretical foundations for practice to caring for the hospitalized adult to shaping the healthcare system through the CNS’s spheres of influence. With a special emphasis on the practical application in clinical practice the author uses a body-system approach to guide readers through evidence-based collaborative and independent nursing interventions within the framework of the CNS role.