Afaf Ibraheim Meleis is an influential nurse scholar born in Egypt in 1942. She developed Transition Theory drawing from nursing, sociology, and other disciplines. Transition Theory views life as a series of passages between different phases or statuses and examines the conditions surrounding transitions. Key concepts include roles, personal and environmental factors, and the nature, types, patterns and indicators of transitions. Transition Theory provides a framework for nurses to help individuals and organizations prepare for and navigate life changes and developments.