12 unselected female patients of extended suicide examined for an expertise testimony (4 schizophrenics, 4 endogenous depressives, 3 personality disorders, 1 psychogenic reaction) were investigated. With the exception of one all schizophrenic patients killed their victims under the influence of hallucinations and/or delusion. In two of the melancholic patients showing personality traits in the sense of the melancholic type (Tellenbach) a duty-bound motive for killing the other, characterized as a hypernomic motive, was found. Apart from this, in these patients a psychotic identification with the victim was given, which induced them to kill the other like themselves with the motive of an unworthy existence. In all patients with a personality disorder and psychogenic reaction the motive of killing others was connected with egocentric personality traits. In all of these patients the killing of the victim or the attempt of killing was precipitated by an event. Two of the patients were addicts. The notion of extended suicide as well as the question of the altruistic motive of killing others are discussed.