Characteristic of the Austrian divorce law is the principle of disruption. This thesis tries to examine the importance of the phenomenon of "irretrievable breakdown" of marriage during a divorce. My work focuses on the one hand on details of the impact of the disruption as a general principle of divorce law. In advance it shows a general overview of the Austrian divorce law and the development it has taken, followed by a general analysis of the "irretrievable breakdown" of marriage.The thesis deals with the special meaning and interpretation of the "irretrievable breakdown" of marriage in the different ways of divorce. For example, in the divorce from of ?§ 49 Ehegesetz? the misconduct of marriage must lead to the irretrievable breakdown. In the divorce forms for other reasons the central issue is the date of entry of the irretrievable breakdown of the marriage. Since the fault in these types of divorce does not matter, the disruption principle is the prevalent theme. As the evaluation of the irretrievable breakdown of the marriage is just both an important and a sensitive topic, this thesis shows, what to consider when examining the irretrievable breakdown of the marriage for the individual species and which distinctive problems can arise.Following the system consisting of the disruption and fault principle is discussed. In this context, the "why" of this mixed system is explored, while also critical voices from the doctrine come into account. Then, using statistics, the most important "numbers of divorce law" are lit.