The legal system is becoming increasingly frayed. It dissolves into ever more specific and smaller individual areas. The overview of the whole threatens to get lost. This development does not spare the law of obligations either. This book attempts to counteract this for the central area of the law of obligations. The framework supplied here can be used to collocate and systematically arrange the numerous and diverse individual legal phenomena with regard to the grounds for extinguishing a debt; it also shows the underlying structures. Here, the focus is not on the well-known reasons for extinguishing debt, "fulfilment" and "fulfilment surrogates", but on the reason for extinguishing debt, "elimination of the debt"