The circumstances in drug-related deaths were investigated in this study. The basic client sample was composed of 743 drug addicts of the opiate type who had been admitted into the institute's drug-free outpatient program from 1969 to 1982. In this program, 91 clients died during the observation period. In order to be able to judge the various backgrounds adequately, a multiply subdivided classification system was developed for the death cases. Each case was recorded in three main categories: manner of death, cause of death, and phase of addiction. This was a more elaborate procedure than those commonly used since, in general, such death cases are only subdivided into a few groups that differ little from one another. Two manners of death predominated in this sample: accidents caused by poison (62%) and suicide (25%). Within in the various causes of death, poison cases prevailed (80%) and opiate intoxication (single or combined) was predominant (60%). Concerning the phase of addiction two phases were distinguished: the actual drug addiction phase (65%) and the intramural stay in prison or a hospital (25%). There were no significant sex-related differences. Various combinations regarding the mechanism of lethal opiate intoxication of drug addicts were scrutinized, concentrating on three approaches: the lack of opiate tolerance after periods of abstinence, the synergistic effect of simultaneously taking other CNS-depressant drugs, and differences in concentration in the heroin used. Our conclusions are given from the point of view of adequate counceling for drug addicts. Bei 91 Todesfällen eines ambulant betreuten Klientels Opiatabhängiger (n=743) im Zeitraum 1969 bis 1982 werden die Umstände des Todes analysiert. Es wird ein über die sonst übliche Betrachtungsweise hinausgehendes vielfach untergliedertes Einteilungsschema entwickelt. Jeder Todesfall wird nach 3 Hauptkategorien erfaßt: bei der Todesart dominieren der Unglücksfall durch Vergiftung (62%) und der Suizid (25%), bei der Todesursache Vergiftungsfälle (80%), wobei die (alleinige oder kombinierte) Opiatintoxikation überwiegt (60%). Bei der Suchtphase zum Zeitpunkt des Todes lassen sich 2 Gruppen unterscheiden: aktuelle Sucht (65%) und intramurale Verwahrung (25%). Das Zusammenwirken dieser 3 Aspekte bei tödlichen Opiatvergiftungen Heroinabhängiger wird untersucht im Blick auf den verminderten Toleranzstatus nach Abstinenzperioden, den synergistischen Effekt sowie der wechselnden Wirkstoffkonzentration des Heroins. Die sich ergebenden Folgerungen bei der Betreuung Abhängiger werden angesprochen.