Rechtsdurchsetzung durch Vertragsstrafe und Aufrechnung

As a rule, the enforcement of substantive law is attributed to procedural law, which ultimately envisages the imposition of state power through steps of enforcement. In addition to this, however, the substantive law itself provides a number of possibilities in order to facilitate the enforcement of rights or, at least, to have formative influence on those rights. Two demonstrative, classic instruments are penalty clauses and the right of set-off (or functional equivalents). A collective comparative analysis of both legal institutions aims to achieve the goal of placing them in their wider context, with reference to the relevant historical development and their relationship with procedural law.