Central banks can go broke. History has given many examples of monetary institutions that went into bankruptcy and have been recapitalized in order to maintain their monetary policy. For a long time, the consequences of central bank insolvency were considered to be an issue reserved for developing economies and unstable economic environments. Only recent developments have brought the subject into the economic debate regarding historically stable and profitable institutions like the Swiss National Bank, which presumably faces a heavy loss for 2015. However, the implications of low or even negative central bank capitalization for performance in regard to monetary policy objectives remain highly elusive and have sparked much discussion. The financial situation portrayed in the balance sheet of a central bank gives little indication of whether the institution has performed according to the stipulated policy goals. Even though research in the field has been somewhat developed in recent years, a well-structured analysis of the question of whether and to what extent central bank capital affects performance does not exist as of this writing. What is lacking is a thorough theoretical framework to assess the empirical evidence from recent studies. This paper tries to fill this gap by examining the fundamentals of central banking and its differences to commercial banking. It is shown that negative central bank capital does lead to poor performance. However, the channels through which it influences monetary policy are complex, and, therefore, a multidimensional model is elaborated. Tested against empirical evidence from previous studies, the model appears to have good explanatory power on how the ability to issue money influences the effects of low capital on inflation. The significance of the currency of denomination of assets and liabilities for performance, on the other hand, has been crucially underestimated in the literature.