The aim of this dissertation is to know whether the decentralized approach, officially put forward in the management of sovereign debt crises since their origin, is not only feasible but also efficient in terms of equity of the debt burden sharing. We define indeed an efficient restructuring process as a procedure of short duration (less than one year) and that meets the needs of both parties. If, in the side of creditors, the discount should not be abusive, towards the debtor, the debt must become sustainable, in both economic and social terms. Field analysis process of renegotiating debt focuses exclusively on Latin American economies, insofar as they represent debtors who historically recorded the highest number of defaults. Through a multidisciplinary approach, we finally defend the thesis that the failure of the various restructuring process is directly subordinate to the iniquity of sharing the debt burden, which is due to an imbalance of bargaining power, as an inherent part of decentralized management. Our macroeconomic and inductive approaches built the framework for socio-economic analysis, which uses history, political economy, but also a study based on social psychology. This dissertation is structured in two parts, themselves divided into two chapters. The first part focuses on understanding the origins of crises, their prevention and crisis management, and then their failures. It combines empirical observation and theoretical underpinnings of the decentralization. Specifically, the first chapter outlines, given the dual responsibility in the onset and sinking into the crisis, the failure of the decentralized approach in the long term. It concludes that not only decentralization is inapplicable, since a third party is always forced to intervene, but nor it does allow an fair sharing of the crisis costs. The second chapter consecutively seeks to understand why such a restructuring process is still maintained. The political economy of decentralization then shows that the choice between regulation and "laissez-faire" is not so much linked to economic efficiency criteria, but rather to ideological and political considerations. The second part of this work symmetrically proposes lines of thought to overcome the main obstacles identified in most cases of defaults and restructurings. Thus, if the third chapter addresses the second, fourth echoes the first. Indeed, the third chapter shows that decentralization can't be efficient, not only because of its technical pitfalls, but also because of the nature of the both contractual parties. Sovereign immunity having been put into perspective in the first two chapters, the point here is to analyze the functioning of financial markets in an alternative way, compared with the efficiency hypothesis. That is why we go into the Keynes psychosocial analysis (1936) in depth with the behavioral finance. Such a study reveals the inability of creditors to organize themselves in good faith, while it is the sine qua non condition of the decentralized approach implementation and efficiency. Therefore, the final chapter concludes on the need for a shift towards a more centralized approach, which includes a neutral, competent and institutionalized third party. Here, if multilateralism must prevail as a model of collaborative thinking, in regard to the management of the current debt crisis in Europe, such a possibility remains unlikely in the short term. This is why debtor countries may have to take some unilateral decisions, including potentially legitimate and transparent debt repudiation in case of sinking into the crisis, in order to compel the international community to make that needed shift. Keywords: Sovereign debt, Restructuration, Decentralized approach, Dependency theories, Political Economy, Behavioral Finance.