This work examines the various implications of the Roman Catholic doctrine of the sanctity of life. Divided into three parts, it examines the documents and theory that constitute the sanctity of life, and how the sanctity of life should protect life at the beginning and at the end. The section dedicated to protecting the sanctity of life at the beginning, tracks the historical development of the Catholic position on abortion, and also discusses the church’s stand on the premature induction of labor and the harvest of fetal tissue for therapeutic purposes. The section dedicated to protecting the sanctity of life at the end examines the history of Catholic teachings on suicide and discusses terminating life support.