Out of Afaf Meleis' forty years of research and practice comes ""Transition Theory"", based on the work of nurses as they manage the developmental, health and illness, and organizational transitions of patients and families. A collection of over 40 articles published from 1975 through 2007, ""Transitions Theory"" covers developmental, situational, health and illness, organizational, and therapeutic transitions. Each category includes an introduction written by Dr. Meleis, the originator of ""Transitions Theory"", in which she offers her historical and practical perspective. Each section also includes a previously unpublished paper, written by an expert in the field. The book concludes with Dr. Meleis' vision for the future of Transition Theory research and practice.