Ch.1. Theory and Methods The first part of this "Practical Guide" is devoted to history, basic theoretical models and clinical and psychological diagnostics of post-traumatic stress. An overview of studies on this problem and Russian-language versions of clinical and psychological methods most often used in world practice are presented. The presented set of techniques was adapted, tested and for many years used in the laboratory of psychology of post-traumatic stress of the Institute of Psychology of the Russian Academy of Sciences. Method forms are placed in the second part of the "Practical Guide." The book is designed for students and specialists.