The emergence of grief as a topic worthy of psychological study is an early 20th century invention. Freud published his influential essay on mourning and melancholia in 1917. Since he proposed the concept of "grief work," contemporary psychologists have examined his theory empirically and have claimed that grief is a pathology that should be included within the psychological domain. How, and why, has grief theory evolved within the discipline of psychology in this way? In what ways do these changes in the understanding of grief coincide with other historical developments within the discipline? In this article, I trace the development of grief, originally conceived by Freud within a psychoanalytic and nonpathological framework, to the current conceptualization of grief within the disease model. I show how grief theory has evolved within the discipline of psychology to become (a) an object worthy of scientific study within the discipline, and subsequently, (b) a pathology to be privatized, specialized, and treated by mental health professionals.