This paper takes stock of the literature on unconventional monetary policies, from their implementation to their effects on the economy. In particular, we discuss in detail the two main measures implemented in most developed economies, namely forward guidance and large-scale asset purchases. Overall, there is near consensus that these measures have been useful, although there are a few dissenting views. Because unconventional monetary policies have left their mark on economies and on the balance sheets of central banks, we offer insights into their legacy and ask whether they have led to a change in “the rules of the game” for setting interest rates and choosing the size and composition of central banks’ balance sheets. Finally, we discuss whether to modify the objectives and the instruments of monetary policy in the future, in comparison with the pre-crisis situation.