The nursing care of patients undergoing surgery is an exacting, difficult and challenging task. But it is also a gratifying experience for a surgical nurse. Due to the advances in anesthesia and in surgical techniques, nurse has the pleasure of seeing patients recover rapidly and return home to a productive life. The four pathologic processes responsible for most surgical conditions are obstruction, perforation, erosion, and tumors. Perioperative nursing is the term used to describe the wide variety of nursing functions associated with the patient\\'s surgical experience. The word perioperative includes the three phases of the surgical experience—preoperative, intraoperative and postoperative. The chapter covers physiologic assessment, diagnostic tests, psychological assessment, legal aspects, nursing diagnosis, nursing interventions, intraoperative care, and postoperative care.