Based on an analysis of the works of E. Fromm, the book offers a description of the existential criterion of normal and abnormal personality. It is shown that this criterion has a fairly high degree of theoretical validity, since in more particular versions it is implicitly contained in the classical personality theories of S. Freud, A. Adler, C. Jung, C. Rogers and W. Frankl. The use of the existential criterion in A study of clients of psychological consultation with child-parent, marital and personal problems, as well as families who have never applied for psychological consultation, allowed us to obtain results that can be considered as empirical reinforcement of the classical point of view that the most important psychological factor influencing the occurrence of a person with many life problems, is the anomaly of his personality, which consists in the inconsistency of its position with the nature of human life. The book is addressed to research psychologists interested in the problem of normal and abnormal personality, practicing psychologists working in the field of psychological counseling and psychotherapy, and students of psychological faculties of universities.