Balint's important work extended over a period of 40 years in two directions; firstly the development of individual sexuality, and secondly, the development of object relationships, together with their relationship to psychoanalytical technique. He introduced the concept of primary love and was one of the pioneers in the thinking of the interdependence of mother and infant. He extended Ferenczi's work on therapeutic regression, introducing the concepts, among others, of benign and malignant regression, the basic fault, and the states of ocnophilia and philobatism. His applied psychoanalytic work is world famous, particularly the Balint groups for general practitioners and similar groups for marital therapists, social workers, and psychosexual counselors.