The author of the book is a psychiatrist-psychotherapist and practical psychologist. His book is fully a guide to the prevention of mental illness. The knowledge set forth in it helps to find ways to understand yourself and others and, therefore, helps to prevent mental breakdowns, nervous crises. The book provides rich knowledge of characterology. It is written in a living accessible language, so it will be interesting not only to psychiatrists, psychologists and psychotherapists, to whom it is intended in the first place, but also to everyone who would like to learn to understand themselves and others. The book can be recommended as a textbook for universities.