In theory, financial globalisation has ambiguous effects on monetary policy. It may dampen effectiveness, but it may also amplify it through exchange rate valuation effects. This column shows evidence that the latter effect has dominated since the 1990s. Financial globalisation has increased the output effect of a tightening in monetary policy by as much as 25%. One implication is that monetary policy transmission mechanisms have changed, with the exchange rate channel gaining importance at the expense of the interest rate channel.