This PhD dissertation is aimed at investigating private penalties and, in particular, punitive damages. These issues, in the past very rarely analyzed by Italian private law scholars in the past, currently represent a field ripe for investigation and constitute the starting point for an evolutionary reinterpretation of the civil liability scheme in our legal system. The first part of the dissertation analyses the concept of legal sanction in a philosophic perspective, and then proceeds with an overview of the remedies provided in the various branches of the Italian legal system. On the basis of these premises, the dissertation proceeds with a description of the instruments and remedies used in private law, among which the concept of private penalty emerges. In order to understand the importance that the sanction with a punitive function assumes in the private law world, it is necessary to start from an analysis of the current regulatory framework. In this direction, the second chapter of this work is dedicated to the deepening, in particular from a functional point of view, of multiple legal concepts - included in the civil code, in the code of civil procedure and in special legislation - which are characterized by pursuing a purpose, at least partially, punitive. Starting from the third chapter, attention is drawn to a particular kind of private penalty: punitive damages. In relation to this issue, there are many aspects that appear problematic, and that indeed have been the subject of broad doctrinal debate and jurisprudential conflict; in particular, with focus on the possibility of enforcing foreign sentences imposing punitive damages and on the direct applicability of the same by the Italian judge. The goal of this work is to theorize an enrichment of the civil remedy by envisioning the potential import of punitive damages into the Italian legal system, in compliance with the principles that govern it. From a methodological point of view, the investigation into punitive damages was carried out by comparing various legal systems. Therefore, the last chapter of the paper is dedicated to punitive damages applied by the courts of the United Kingdom and the United States, in particular because it was in these common law countries that the legal institution of punitive damages was originated and developed. The dissertation concludes the study of punitive damages in other foreign legal systems and, with particular regard to some countries adopting a civil law system, noting that in recent times there have been some significant openings that invite a deeper reflection.