The global financial crisis has had lasting impacts on the global economy and how we think about it. In its wake, the resulting surge in government debt in many countries has been accompanied by lower, rather than higher, interest rates and subdued inflation pressures. These events have sparked questions about the validity of conventional economic theories, opening the door for new, and at times radical, theories to emerge; a trend that has only been heightened by the current global COVID-19 pandemic. One such theory that has been at the centre of public discourse is Modern Monetary Theory (MMT). It has gained popularity as part of the “green new deal” discussions and is now garnering even more attention in the midst of the COVID-19 crisis, where the issuance of government debt has burgeoned. MMT is controversial and, as such, has been subject to different understandings and interpretations. In this paper, we attempt to discern what MMT really is from what it is not, and provide a primer on its core tenets with respect to its views on the role monetary policy and public debt management. MMT is commonly assumed to be about printing money while ignoring any inflationary consequences. This is largely a result of its politicization and is an incorrect understanding of the theory. Contrary to common misconceptions, MMT actually accepts that government deficits matter, and acknowledges the need to contain inflation. In its simplest form, MMT argues that a monetary sovereign government – one that issues its own currency, borrows mainly in that currency, and operates a floating exchange rate – does not face financial constraints. Instead, it concedes that governments will face a real constraint on spending when aggregate demand reaches the economy’s aggregate supply, which, if surpassed, would lead to inflationary pressures. Unlike conventional thinking, however, MMT prescribes fiscal measures, such as raising taxes or cutting government spending, to deal with these pressures. Rather than tasking independent central banks with achieving full employment and controlling inflation, MMT puts the onus squarely on fiscal authorities to accomplish those tasks. While MMT believes deficits matter, it does not view a deficit that temporarily increases the debt-to-GDP ratio while increasing productive capacity as a sign of overspending. Rather, MMT views excess capacity in the economy as a sign of underspending by the government. With this understanding of MMT in mind, we find that MMT overstates the degree of monetary sovereignty that governments like Canada, with a small and open economy, enjoy in a world where capital is mobile. In addition, we argue that having an independent central bank tasked with an explicit inflation control mandate is essential for a well-functioning economy to anchor market perceptions about inflation. This anchor is less likely to hold fast if the task of controlling inflation is solely left to fiscal policymakers who might hesitate to raise taxes or reduce spending in the face of rising inflationary pressures and prices