WASHINGTON -- The economic team that President-elect Barack Obama unveiled Monday, led by Lawrence Summers, Timothy Geithner and Christina Romer, is composed of widely respected, centrist economists who until recently advocated cautious, sensible-shoe policies to do such things as boost savings, reduce deficits and allow markets maximum feasible rein.

But the assignment that Mr. Obama has given them is anything but cautious and sensible-shoe.

It is to make Washington, D.C., the consumer of last resort in an economy where consumption is plunging. It is to devise industrial policylike programs to salvage a collapsing auto industry and turn green an energy industry almost wholly focused on fossil fuels. It is to dip more deeply into the lives of ordinary Americans -- especially those with housing troubles -- than the government has done in generations.

But so much has gone so wrong during the past 15 months that what would have been beyond the political pale as recently as a few years ago quickly is becoming the consensus.

"These are not moderate, centrist times so economists who in normal times are moderate and centrist, aren't going to act that way now," said J. Bradford DeLong, a University of California, Berkeley, economic historian and prolific economic blogger. "The wild-eyed radicals are looking pretty sensible."

Mr. Summers will be Obama's chief economic adviser, Ms. Romer will chair the White House Council of Economic Advisers and Mr. Geithner is Obama's nominee for Treasury secretary.

Their underlying task is to reconcile the nation's historic commitment to free markets even as the government is intervening ever more deeply in the financial system, in individual companies and in people's lives.

"Larry and the rest have to re-strike the balance that FDR sought in the New Deal of harnessing the market's potential while at the same time damping its destructive social impulses," said Robert Z. Lawrence, a prominent Harvard economist.

That means the new administration must navigate uncharted and uncomfortable terrain. It must thread its way, for example, between calls for an expensive health-care overhaul and pressure to boost the economy with more deficit spending. It must deal with union demands to rewrite labor laws while trying to coax businesses into expanding. And it must satisfy environmentalists who want "green" policies even at the cost of economic growth.

The three economists must do all of this, and they must do it much more quickly than almost anyone had imagined only a few months ago.

In announcing his economic picks, Mr. Obama, who had intended to lie low during the final months of the Bush administration, acknowledged he had been forced to show his economic hand much earlier than he had intended.

No sooner had the president-elect thanked the three for accepting their new positions than he informed them that their work "starts today."

The idea of a big new fiscal stimulus -- gargantuan by historical standards -- is the first and least controversial step the new administration could take.

With President George W. Bush's $168 billion stimulus of earlier this year having worn off and the financial crisis having stalled both U.S and world growth, there is essentially no other actor but the federal government that can get the economy going again, many experts and lawmakers believe.