In our case, the ultimate goal of these operations is to bring back medium-term inflation in the euro area to levels close to, but below, 2%, in line with our price stability mandate. Monetary policy is implemented in normal times in money markets by buying and selling short dated securities or, in the case of the ECB, by lending to banks against adequate collateral.
While the ultimate goal is the same, when the lower bound is reached the actual implementation of monetary policy also has to take place in bond markets, which central  BIS central bankers’ speeches  1  banks in normal times only affect indirectly. Stepping into this new domain creates certain challenges and might even have unintended consequences.