When published in 1971,Principles of Paleontology (POP)by David Raup and Steven Stanley revolutionized both textbooks and teaching in paleontology by adopting an approach that focused on theprocess of studying biologic groups, rather than asystematic approach(the study of individual groups of organisms), or anhistorical approach(narrating events to date). For thishighly anticipated revision of Raup and Stanley's one-term undergraduate text, two of Raup's former studentsMichael Foote and Arnold Milleruse that defining core approach to present a thoroughly up-to-date portrait of a field that has undergone major transformations in the last two decades.