We present a model of the maturity of a bank's uninsured debt. The bank borrows to invest in a long-term asset with endogenous and nonverifiable risk. This moral hazard problem leads to excessive risk-taking. Shortterm debt may have a disciplining effect on risk-taking, but it may lead to overborrowing and/or inefficient liquidation. We characterize the conditions under which short- and long-term debt are feasible, and show circumstances where only short-term debt is feasible and where short-term debt dominates long-term debt when both are feasible. The results are consistent with some features of the period preceding the 2007-2009 global financial crisis.