With the adoption of a common currency the degree of substitution between financial instruments supplied by EMU Member States to finance their national debts has risen. Providing the market for euro-denominated government securities with a large volume of similar financial instruments is likely to increase liquidity and lower yields. By contrast, providing an excessive volume of the same instrument might increase the return demanded by investors. This paper aims at empirically assessing the balance between liquidity and overcrowding effects by EMU countries’ issuance plans. Our results document a significant relationship between bunching in issues and bond yields.