URL des Documents de travail : http://ces.univ-paris1.fr/cesdp/CESFramDP2009.htmDocuments de travail du Centre d'Economie de la Sorbonne 2009.79 - ISSN : 1955-611XThis paper establishes, in the context of the Diamond (1965) overlapping generations economy with production, that the risk that savings in unbacked assets (like fiat money or public debt) become worthless implies that, not only the first-best steady state, but even the best steady state attainable with those saving instruments fails to be a competitive equilibrium outcome under laissez-faire. It is nonetheless shown as well that this best monetary steady state can be implemented as a competitive equilibrium with the adequate policy of taxes on returns to capital, subsidies to ret...