The quantity theory of money implies that sustained inflation requires a sustained increase in the money supply. It does not, however, imply that the reverse is also true. This column explores and illustrates this issue by comparing inflation in the US following the collapse of Lehman Brothers with Germany’s hyperinflation experience after WWI. A key factor explaining the vastly different inflation experiences is how the monetary expansion translated into demand. The Fed’s base expansion did not translate into demand for goods and services, whereas the German monetary expansion was motivated by the government’s hunger for seigniorage revenues.