Bank stress tests in the US were an important tool for bailing out banks in the Great Recession. As this column points out, however, because the tests use regulatory rather than market measures of asset values and risk they have almost nothing to do with whether a bank will be economically solvent under test conditions. This column argues that the thousands of pages of post-crisis bank regulation have largely ignored perhaps the two most needed reforms: measuring asset values and risks in an economically realistic way. Reforming the stress tests is necessary for clearly and credibly placing responsibility for future banking losses in the private sector and for improving incentives for both managing old risks and for investing in new ones.