As the Federal Reserve weighs an imminent cut in its extraordinary economic stimulus, many outside the United States are pleading with the Fed: "Would you consider the impact on us too?"
Speaking at the Fed's summer conference in Jackson Hole, Wyo., Lagarde turned the spotlight on what has emerged as the main global economic issue of the day — the bold actions of central banks and, as she put it, how these policies "in one corner of the world can reach all corners."
Although the IMF's managing director spoke generally about central banks, it was clear that she was focused on the Fed and the widespread expectation — some would say fear — that it will start scaling back a massive bond-buying program next month.
The monthly purchases of $85 billion in Treasury bonds and mortgage-backed securities have helped hold down long-term interest rates and, until recently, kept emerging markets flush with cheap money.
In recent weeks, as interest rates in the U.S. have jumped in anticipation of the Fed's tapering of stimulus in September, investors have pulled cash from India, Brazil, Indonesia and some other developing economies. That has resulted in steep declines in their currencies.
The rise in interest rates and the flow of capital back to the U.S. and other developed nations aren't just related to the Fed.
They reflect the somewhat brighter growth prospects in developed economies, Europe and Japan included, while the rapid declines in emerging-market currencies point to some long-standing structural and financial challenges in those countries.
Still, there's little question that the Fed's unprecedented flood of cash into the financial system since the recession has rippled across the globe.
Previously, the easy money sometimes prompted complaints from developing nations that there was too much capital flowing into their markets, bringing inflationary pressures and hurting exports as their currencies rose in value.
Now, however, the concerns for Lagarde and many others are a rapid reversal of capital flow and the increased risks of a sharp economic slowdown in emerging markets.
"Even if managed well," Lagarde said, a central bank's exit from easy-money policies could still present an "arduous obstacle course" for other countries. Lagarde said that what's needed is greater policy coordination and cooperation for the sake of the entire globe.
"No country is an island," she said in prepared remarks. "Looking at the wider effect is in your self-interest. It is in all of our interests."
Lagarde delivered her address to central bankers from around the world, as well as other foreign dignitaries, economists and investors, at the opening luncheon of the Fed conference.
Notably absent from the meeting was Ben S. Bernanke, who is expected to step down as Fed chairman when his second four-year term expires in January.
The Fed's vice chair, Janet Yellen, a top contender to replace Bernanke, is at the gathering but not expected to give a speech. Another front-runner for the job is former Treasury Secretary Lawrence Summers, who is not attending the annual symposium set in the Teton Range.