Fortunately, we have not been driven there. That tool kit would be opened up if we ended up having interest rates at zero. Indeed, what we've seen in a number of countries now is that we've discovered that zero may not be the actual lower bound, which...of course, again, this has never been done before so now we have negative interest rates in some countries.
Quantitative easing as a general concept means building up the central bank's balance sheet and putting more of those funds into the marketplace, and then watching the system use them. But every financial system is different, and so “made in Canada” might mean that we would choose specific types of assets to buy because we're trying to do what we call “qualitative easing”, which means asking where the problems are, which the U.S. did some of in order to try to make credit move faster in areas where there was a gridlock, if you like.
Quantitative and qualitative easing make for a wide range of possibilities in any situation. As I say, quite fortunately we have not been anywhere close to that need.