Emotions are interactive, spontaneous and contextual. Its comprehensiveness should be articulated by dynamic interpretation of emotionality rather than a static and description of emotions by reductionistic measurement and scales. The same applies to the emotions of persons with mental illness. This book describes various perspectives and conceptual underpinnings of emotionality including evoluntionary, initial psychological, psycho-evolutionary, cognitive, psychodynamic, structural and post-structural, as well as phenomenological perspectives. In each perspective, its implications on emotionality of persons with mental illness are thoroughly discussed. Furthermore, this book includes a full discussion of a multi-dimensional model of emotionality.