This paper reviews arguments for and against attributing an explicit financial stability objective to monetary policy. The discussion is conducted from the perspective of middle-income countries (MICs), where bank credit plays a critical role both on the supply and demand sides. It also discusses, on the assumption that a more proactive role is desirable, what monetary policy should react to and to what extent it should be combined with macroprudential regulation. There are robust arguments in favour of monetary policy reacting in a state-contingent fashion to a measure at the private-sector credit gap, not only because of financial stability considerations but also because of the high degree of uncertainty regarding real-time estimates of the output gap in MICs. Nevertheless, monetary policy is not a substitute for macroprudential regulation; in particular, it cannot address the cross-section dimension of systemic risk.