OTTAWA - They've been dubbed the "accountability" summit and the "austerity" summit, but as Prime Minister Stephen Harper prepares to host historic back-to-back, high-level meetings this week, he risks appearing neither austere nor accountable.

For 72 hours, the world's most powerful people will surge into Southern Ontario, complete with enormous entourages, and thousands of journalists in tow.

First, leaders from the G8 rich countries -- plus 10 guests from developing nations -- will hold their "accountability" summit on Friday afternoon and much of Saturday near Huntsville, Ont., at a lakeside in cottage country. They'll discuss peace, security, and maternal health, with an emphasis on proving how well they can keep their promises.

Then, they'll zip down to Toronto for a larger Group of 20 meeting on Saturday night and Sunday, dining at the stately Royal York Hotel, and then gathering at the more functional Metro Toronto Convention Centre.

There, they will wrangle over how to control ballooning deficits, stabilize banks, and open up the wallets of Asian consumers. If Harper has his way, the deficit countries will commit to a decade of austerity, so the global economy can get back on track.

On the other side of the traffic-disrupting fence erected around the summit site, most of the citizens of Toronto are making themselves scarce, warned to stay away by the massive security operation required to guard well over 30 heads of state and international leaders. The streets will fill instead with demonstrators, taxis, limos and the tens of thousands of support staff that are needed to keep the summiteers comfortable.

Security will be omnipresent, partly to deter protesters from destroying property or getting too close to the leaders. Activists have been organizing for months, with diverse labour and anti-poverty groups planning stunts and loud demonstrations.

The 3000 or so journalists covering the events, meanwhile, will be making a bee line for the infamous Fake Lake to see if it lives up to its billing.

Ottawa is spending more than $1.24 billion on the two events, including $1.9 million on a "marketing pavilion" inside the media centre that includes a fake Muskoka lake and dock, decorative canoes, a bar, and a replica of the Toronto Stock Exchange.

Most of the billion is being spent on security, although Ottawa has not released many details about how the bill has risen so high - despite the government's fixation on accountability for world leaders.

Still, the "water feature" has become the focal point for critics on the right and the left, who say Ottawa is being frivolous and lavish, spending money it doesn't have to cover up bad decisions made on logistics.

"I don't think it's credible to preach restraint, when your actions say the opposite," said Liberal finance critic John McCallum recently. "It's not only made Stephen Harper a bit of a laughing stock, but since he's the prime minister, it's made Canada a bit of a laughing stock."

So the pressure is on to produce solid results from the summits.

"Failure to deliver is not an option," Harper wrote in a letter to G20 leaders last week. "We have a responsibility to our citizens, and indeed to all citizens, to strive for the best possible outcomes."

The main accomplishment at the G8 summit will be an aid package to improve the health of mothers and babies in developing countries, says Janice Stein, director of the Munk School of Global Affairs at the University of Toronto.

The idea of the G8 pumping money into a forgotten, desperate and worthy cause has been widely accepted, Stein said, but Ottawa is having trouble attracting donations.

Canada has put $1 billion on the table, sources say. And while that's less than the amount Ottawa is spending to host the summit, and less than aid groups say is Canada's share of what is needed, it's more than other cash-strapped governments seem willing to part with.

"The real issue is, what happens on maternal and child health, and how much will be put on the table," Stein said. "Canada is the lead donor here. The Europeans are not there yet."

Ottawa hasn't given up, Stein added, especially since the so-called Muskoka Initiative is Harper's signature on the summit.

"They're still working to get those commitments in place."

Concrete results from the G20 summit are equally up in the air.

If the G20 has any hope of establishing itself as an international body that is useful for more than just putting out fires like the global financial crisis, it has to agree to substantive economic and financial reforms, says Wendy Dobson, co-director of the University of Toronto's Institute for International Business.

After months of deadlock over how much key countries would sacrifice for the good of the global economy, there were signs on the weekend of progress.

The United States has presented the G20 with a medium-term fiscal plan to control its deficit. Harper has put hard numbers to his request that all indebted G20 countries act to control their debt loads. And on Saturday, China signalled it was ready to make small adjustments to its currency.

But it remains unclear whether the recent show of good will is enough to make everyone happy. And the countries have yet to put aside their differences about financial regulations, Dobson said.

The G20 can easily reiterate principles that they've agreed to in the past, but true progress, with numbers and targets and timelines attached, will take hard-core negotiating down to the last minute, said Tom Bernes, acting executive director at the Centre for International Governance Innovation in Waterloo, Ont.

"They have to deliver and show they are more than a crisis committee," Bernes said. "It is a testing ground."

Not just for the G20 but Harper too.