The authors present a study of problems of the surgical treatment of acute and chronic instabilities of the knee joint. In cases of recent injuries 32 operations of restoration of the cruciate ligaments and the bursal and ligamentous apparatus were made: in most cases the long-term results were good. The authors believe that timely and adequate treatment of the patients during the acute stage of the disease will allow to bring the problem of the treatment of chronic instability of the knee joint in most patients closer to its practical solution. In primarily anterior and posterior chronic instability associated with a light degree of lateral instability an operation after Augustino is advised, particularly as modified by the authors, as an independent operation or as one of the elements in complex reconstructive operations in the multiplane forms of instability of the knee joint. A detailed description of the surgical technique is given.