This book is comprised from a number of international contributions which come from diverse paradigms and country backgrounds (Greece, Italy, Portugal, Spain, Netherlands, Bulgaria, US and Australia). Authors are outstanding scholars in their field affiliated with leading academic institutions. The first section is structured on the basis of humanities, existential phenomenology, socio-analysis as applied to clinical psychopathology, and to the psychopathology of everyday life. The major goal of that section is to raise theoretical issues regarding the borderline between psychopathology in common sense in medical sensu stricto. The second and third sections refer to epistemological foundations of explanation and understanding of psychiatric nosology with an emphasis on translation, categories, validity and taxonomy. The section on empirical perspectives presents evidence from several original research trends such as quantitative assessment of psychomotor activity and chronobiology applied to psychiatry as well as potential risk biomarkers for psychiatric diagnosis. This book has been developed upon expert commitment which aims to unify those diverse views in the field under mutual understanding and critical exchange of ideas for the benefit of human knowledge. In summary, this book offers a challenging view of the scope of psychiatry as a complex and controversial dialectic of post-modern disciplinary approaches.