Background: In light of new editions of the DSM and ICD classifications of diseases being prepared, certain clinical entities are being reassessed. Among others, clinical entities under reexamination are Disorder of Extreme Stress Not Otherwise Specified (DESNOS) or Complex PTSD according to the classification of the American Psychiatric Association. The corresponding diagnostic entity of the ICD would be Enduring Personality Change After Catastrophic Experience, which, according to definitions, occurs as a psychological effect of psychotraumatization and excludes the presence of PTSD. Day-to-day clinical practice casts doubts as to the view that PTSD and DESNOS/EPCACE symptoms are mutually exclusive. Aim: To determine possible presence of Disorders of Extreme Stress Not Otherwise Specified (DESNOS) in Croatian war veterans who suffer from combat-related Posttraumatic Stress Disorder (PTSD). Methods: The research included 355 participants in four clinical centers in Croatia. It was based on the following instruments: Structured Interview for Disorder of Extreme Stress (SIDES-SR) and International Neuropsychiatric Interview (MINI), Questionnaire for personality disorders DIP-Q, Quality of Life questionaire (MANSA), Traumatic Antecedents Questionnaire TAQ, Harvard Trauma Questionnaire (HTQ): Croatian Version and General Demographic Questionnaire. Results: Forty three percent of veterans of the Homeland War in Croatia who suffer from PTSD met criteria for DESNOS. At the clinical level, tested veterans met the criteria for the following personality disorders: paranoid, schizotypal, borderline, and obsessive-compulsive and avoidant. Veterans with pronounced DESNOS have more often expressed symptoms of personality disorder as follows: borderline, paranoid, and obsessive-compulsive, avoidant and schizotypal. The veterans who fully meet the criteria for DESNOS, at the clinical level meet - with listed personality disorders - criteria for schizotypal personality disorder. Posttraumatic symptoms affect mostly the expressiveness of personality disorders. Enduring personality change symptoms are more pronounced in subjects who were more traumatized. Persons, who suffer from both, PTSD and DESNOS, twice more frequently suffer from comorbid depression with melancholic features or social phobia. DESNOS patients are almost three times more likely to have the diagnosis of current panic disorder. Furthermore, veterans who have more comorbid disorders with PTSD, have more pronaunced permanent changes in personality due to trauma. Less satisfaction with quality of life can be predicted in subjects with early trauma and more pronounced symptoms of PTSD or DESNOS. Conclusion: The research results demonstrate that PTSD and DESNOS can occur in comorbidity, which is in contrast with the ICD-10 criteria. A higher intensity of symptoms and a more frequent comorbidity with other psychiatric disorders, especially depression, panic disorder and social phobia require additional therapy interventions in treatment processes for DESNOS veterans.