The paper measures the cost of business cycles by asking what proportion of consumption representative households, whose head is currently employed, would be prepared to give up to avoid the risk of unemployment. Previous estimates by Lucas suggested that the costs of macroeconomic fluctuations measured in this way are surprisingly small. The first part of the paper presents a critique of the Lucas aggregate method showing that his estimates are not robust. An alternative disaggregated framework is then developed and shows that the costs of macroeconomic fluctuations are significantly higher than those obtained by Lucas. Consequently, the view that inflation 'matters' whereas business cycles are unimportant events is questioned. Copyright 1994 by Royal Economic Society.