The income velocity of money-an inverse measure of the demand for money balances-is the ratio of the money value of income to the average money stock that the public (excluding banks) holds in a given period. Why the magnitude of that ratio has changed over time is the subject of Michael D. Bordo and Lars Jonung's classic study, originally published as The Long-Run Behavior of the Velocity of Circulation. Supported by statistical data, econometric estimation techniques, and meticulous historical analysis, this work describes, in an international setting, how slow-moving economic, social, and political forces interact with the decisions households and firms make about how much money to hold. Annual time series of velocity for several countries from the late nineteenth century to the late twentieth century display a U-shaped pattern. Existing theories can explain each section of the velocity curve-the falling, flat, and rising parts-but the overall pattern is not consistent with any one