A brief history of child and adolescent psychiatry is traced, from old ages to modern times. In the first part, published in issue no. 125/2014, the origins of child psychiatry and its developments in the United States and in Italy (with the two areas of interest, mental retardation and juvenile delinquency) were traced. In the second part, published in issue no. 126/2014, the developments in the United States are discussed more in detail, mentioning the influence of psychoanalysis, the Child Guidance Movement, etc.; in particular, the child and adolescent psychiatry sections of the Diagnostic and Statistical Manuals (DSMs) of the American Psychiatric Association are described. In this third and last part the International Classification of Diseases (ICD) and the Psychodynamic Diagnostic Manual (PDM) are presented, and the bibliographical references of all three parts is published
Keywords: Child and adolescent psychiatry, history, diagnosis, International Classification of Diseases (ICD), Psychodynamic Diagnostic Manual (PDM)