This article investigates some of the causes of the financial crisis – global imbalances and unsatisfactory regulation of world liquidity – and supports the need to reform the present asymmetric international monetary system based on the dollar as a dominant reserve currency. Part I examines global imbalances, the causes of the US external deficit and the consequences of the international monetary asymmetry. Part II seeks to overcome this asymmetry and the Triffin dilemma by examining two models for a new world monetary system: an international model, without a world central bank (WCB), and a supranational model with a WCB. Two urgent reforms are proposed: the adoption of a global monetary target for the industrialised countries and This article investigates some of the causes of the financial crisis – global imbalances and unsatisfactory regulation of world liquidity – and supports the need to reform the present asymmetric international monetary system based on the dollar as a dominant reserve currency. Part I examines global imbalances, the causes of the US external deficit and the consequences of the international monetary asymmetry. Part II seeks to overcome this asymmetry and the Triffin dilemma by examining two models for a new world monetary system: an international model, without a world central bank (WCB), and a supranational model with a WCB. Two urgent reforms are proposed: the adoption of a global monetary target for the industrialised countries and the issuing of UN Bonds to allow countries to substitute dollar reserves with SDR reserves.