Due largely to developments made in artificial intelligence and cognitive psychology during the past two decades, expertise has become an important subject for scholarly investigations. The Nature of Expertise displays the variety of domains and human activities to which the study of expertise has been applied, and reflects growing attention on learning and the acquisition of expertise. Applying approaches influenced by such disciplines as cognitive psychology, artificial intelligence, and cognitive science, the contributors discuss those conditions that enhance and those that limit the development of high levels of cognitive skill.