Mental health service in Russia was launched at the end of the 20th century, and it has been developing in the sphere known as 'socially-oriented psychiatry' or 'society-based psychotherapy', which implies the transference of the most patient's rehabilitation process from hospital to extramural conditions and practical implementation of this processes in a form of ambulance service for patients with mental disorders. The form of ambulance service allows to perform comprehensive diagnosis of a patient, which can optimize the choice of a rehabilitation program with the help of effective multidisciplinary interaction of members in a semiprofessional brigade (taking into account the areas each member specializes in), which is devoted to the optimization of psychological (biopsychosocial) functioning of a patient. The latter is an important characteristic of functional diagnosis that can vividly demonstrate the rehabilitation potential of a person. Comprehensive analysis of three components of psychic adaptation (clinic-biological, clinic-psychological, and social) and their internal interaction allowed to explain personal functional adaptation profile for various endogenous disorders. The comprehensive diagnosis approach used in the current research clearly demonstrates the definite reciprocal connection between biological and psychological characteristics, which define social adaptation of patients. In addition, there is a statement that to a considerable extent, social adaptation of patients with schizophrenia is connected with clinical characteristics of a disorder, the density of which gradually decreases for a schizoaffective disorder, and is minimal for bipolar affective disorder. On the contrary, psychological adaptation characteristics are of great importance for social adaptation of people with bipolar affective disorder; they are least distinct for people with schizophrenia, with the neutral position for patients with schizoaffective disorder. Cognitive behavioral therapy for patients diagnosed with endogenous disorders can be a part of their rehabilitation program; thus, increasing their rehabilitation potential along with the quality of life.