This chapter explores the essential aspects of pain assessment and management, from defining what pain is to discussing various ways in which pain can be relieved. It emphasizes the individuality of the pain experience and explains how pain is felt, recognising the complexities of the pain experience. The chapter outlines how pain is assessed and indicates the factors that can influence both the perception of and the response to pain. It recognizes the factors that can influence the nurse’s perception of patients’ pain, indicates the types of analgesia used to relieve pain, and explains how these drugs work. The chapter outlines the methods of administration of analgesia, considers the advantages and disadvantages of each method and shows an understanding of other methods used to relieve pain. The nurse plays a major role in managing pain, mainly in terms of determining how best to deal with a patient’s pain on an individual basis.