This paper examines the effects of monetary policy shocks on output in the three largest euro area economies – Germany, France and Italy (EMU3) – by applying a new VAR identification procedure. The results show that monetary policy innovations are at their most potent in Germany. However, apart from Germany, it remains ambiguous as to whether a rise in interest rates concludes with a fall in output, showing a lack of homogeneity in the responses. Homogeneity in response to a monetary shock is crucial in a one-size-fits-all framework. Nonetheless, the lack of similarity between the responses, which is hypothesised to cause de-synchronised business cycles in optimal currency area literature, is often based on the premise that monetary policy itself is a major source of business cycle fluctuations. This paper concludes that monetary policy innovations play, at most, a modest role in generating fluctuations in output for the EMU3. Consequently, it is less important whether the effects of monetary policy are homogenous.