A review of the literature showed that there is no good systematic study of a series of rigorously diagnosed “kleptomaniac” persons, other than those referred by the courts for expert opinions. This applies in particular to German-speaking and other European countries. We therefore report here on the phenomenology, demographics, psychopathology, family histories, treatment histories, behaviour therapy oriented analyses, and treatment results of 12 individuals meeting Diagnostic and Statistical Manual (DSM)-III-R criteria for kleptomania. All patients described an uncontrollable impulse to steal and a reduction in anxiety or tension during or after the act. All had at least one further psychiatric diagnosis. Although the kleptomaniac symptomatology did not seem to be part of these other disorders, the extent of stealing corresponded (positively or negatively) to other psychiatric symptoms such as depressive feelings, excessive urges to eat or migraine attacks. Microanalysis of the act of theft, as well as the preceding and following events (explored by applying behaviour therapy oriented analysis) showed intraindividually consistent, but inter-individually differing triggering factors. There was no evidence of correlation with obsessive-compulsive disorders, but some indications that kleptomania may be associated with affective disorders in terms of an “affective spectrum disorder”. According to a broader definition of “multi-impulsive-disorder” (analogous to Lacey and Evans or Fichter et al), one third of the patients might be diagnosed as “bi-impulsive disorder”. Eight of the 12 patients could be investigated at a mean follow-up time of 2 years after discharge showing favourable results. In conclusion, kleptomaniac behaviour seems to be multiconditionally caused and sustained.