Posttraumatic stress disorder (PTSD) was officially proposed as separate diagnosis in DSM-III, although the clinical consequences of trauma were recognized since ancient times. After its identification in DSM-III, the neurobiology of chronic PTSD has been area of increasing investigation. Earlier the psychoanalytic model of explanation and treatment mostly prevailed. Epidemiological studies show high prevalence of PTSD in general population and specific groups exposed to the traumatic events (survivors of war trauma, natural disasters, terrorist attacks, etc.). Trauma and its consequences affect significantly individual health and functioning, and whole society. The diagnosis of PTSD may have several subtypes, including psychotic symptoms, depending upon pre-existing psychiatric disorder, trauma severity and duration, comorbidity, post-trauma social environment, etc. The role of trauma as an etiological factor in other psychiatric disorders and symptoms remains to be clarified. This paper presents the diagnostic and therapeutic issues in relation to the stress-related disorders with the emphasis on our own experiences in the diagnostic assessment and treatment of psychotraumatized persons (establishing more precious diagnosis of PTSD and comorbid diagnoses, differential diagnoses, different models of treatment in the community and institutions after massive traumatization, including “Croatian model”, treatment of PTSD with psychotic features with novel antipsychotics, etc.).