Emil Kraepelin, a German Psychiatrist, may be considered as the grandfather of Diagnostic and Statistical Manual for Mental Disorders (DSM). Before the DSM was published, he had already an attempt of classifying mental illnesses by grouping its similar symptoms. He had developed a system to make distinctions of different disorders. He believed that biology and genetics have a key role in mental illnesses. This concept became the basis of the DSM-III, which is quite different from earlier versions that are pyschodynamically oriented.