Mira Sorvino.

If there’s one force that can affect social change, it’s a bunch of tech types ripped away from their computers and interfacing with one another. Inspired, perhaps, by the monumental leaps forward the TED conference has given our society, the Social Good Summit, presented by web concern Mashable, overlaps with the United Nations’s General Assembly in timing as well as some speakers. Former prime ministers of Poland and Norway, intellectual bon vivant Jeffrey Sachs and UN Goodwill Ambassadors Forest Whitaker and Mira Sorvino will all be addressing Mashable readers and other concerned citizens of the globe. Don’t worry if you can’t make it out today (Indian summer weekend on Fire Island?)—the conference continues tomorrow with Deepak Chopra and Ugly Betty’s America Ferrera.

Kaufmann Concert Hall, 92nd Street Y, 1395 Lexington Avenue, event runs Saturday through Monday, tickets and information can be found at socialgoodsummit2012.eventbrite.com.

— Actress Connie Fisher Stevens, who was once married to the singer Eddie Fisher, sold her 2,500-square-foot penthouse at Millenium Park for $7 million, The Real Deal reports.

— Make-up magnate William Lauder, CEO of Estée Lauder, has sold his apartment at 730 Park Avenue to his former wife, Karen Lauder, for $15 million.

clewis@observer.com

The documentary, narrated by Martin Sheen, argues that economic imperialism is the cause of widespread poverty in the Southern Hemisphere. According to the film, international economic policymakers at the IMF and World Bank ransom the natural resources of poorer countries, using coercive loans and crushing debt. At the same time, “structural violence” left over from colonialism has rendered these nations helpless, passive witnesses to their own despoliation.

In describing 500 years of the West’s unalloyed villainy, the film turns to a long roster of experts—from Nobel prize winner Amartya Sen to John Perkins, author of Confessions of an Economic Hit Man. The documentary alternates these experts with impoverished people from places like Brazil, Kenya, and Tanzania, who tell their stories of hardship. The film seems to be at pains to give equal billing to experts and ordinary people. But when spliced into the film’s lengthy discussion of the historical roots of inequality, these present-day narratives feel slightly out of place.

The movie’s title, a reference to Columbia economist Jeffrey Sachs’ 2006 bestseller, The End of Poverty, is not meant as an homage. With its provocative question mark, “The End of Poverty?” is intended as a rebuttal of Mr. Sachs’ prescription for alleviating poverty through mosquito nets and fertilizer. “Of course, I have nothing against mosquito nets and fertilizer, but for the fact that we tried that for the last 100 years, and it didn’t change anything. In fact, it became worse,” the film’s director, Phillipe Diaz, said after the screening.

The director’s real target is neoliberal economic policy, championed by Mr. Sachs in the 80s and 90s, which promotes privatization and globalization. In particular, Mr. Diaz is hostile to the idea that natural resources can be owned by a corporation—one of the film’s experts, Clifford Cobb, advocates a return of “the commons,” an ethos of shared ownership. In this, the movie echoes the ideas of the 19th-century economist Henry George; the documentary was financed by the Robert Schalkenbach Foundation, which promotes George’s philosophy.

In an interview with The Observer, Mr. Diaz pointed out that the foundation allowed him complete editorial freedom. “I told them right away, if they want me to make a movie on the ideas of Henry George, I’m not the right person,” Mr. Diaz said, although he acknowledged the influence of George’s ideas on his own thinking about private property.

Despite its title, the film is short on prescriptions for improving the situation. Mr. Diaz suggests that violent uprising is likely, but does not propose a system for the imagined revolutionaries to install in the place of late capitalism. One of his experts, Serge Latouche, suggests that the West submit to a diet of “de-growth,” in which Americans would work and consume less. But Mr. Latouche’s idea isn’t given much time in the film, leaving the specifics vague.

In a question and answer period after the film, the earnest East Village audience pressed Mr. Diaz on questions of doctrine. “There’s no reason to think that over-consumption is the problem, and you’re misleading people with that,” one irritated viewer complained. Another suggested that Mr. Diaz was preaching to the choir, and questioned whether he would be able to inspire real change with his film.

“We put ourselves in this situation,” Mr. Diaz said. “Our system is based on the resources of the South. Unless we can change that, we will arrive with this war over resources and this permanent terrorism.”

De Blasio, along with the majority of the Council, will be term-limited out of office in 2009. He was a key figure in Hillary Clinton's first Senate campaign, has White House experience and has strong ties to labor. Though he’s been talked about as candidate for Brooklyn borough president, he still hasn’t made it clear, officially, what he’ll be running for.

Extra credit for the name given to de Blasio’s top fund-raisers: "Super Good Friends."

“Mostly, [Mr. Pitt] listened,” said Mark Cane, the chief physical scientist at Columbia’s International Research Institute for Climate and Society, who created the first numerical model to predict El Niño. “He’s a very serious young man with a desire to do some good.”

And what celebrity doesn’t want to do some good these days?

From Leonardo DiCaprio’s environmental agitation and Bono’s campaign to eliminate Third World debt and AIDS, to George Clooney’s calls for intervention in Darfur and Madonna’s adoption of a Malawian child, the news and gossip pages are abuzz with celebrities’ public munificence. Even 50 Cent, that self-described “hustler,” has weighed in on the risks of childhood obesity.

And the occasional hypocrisy and self-promotion aside, isn’t anything that brings attention to the world’s ills—global warming, Parkinson’s, African poverty—a good thing?

“I find it odd that we’re inclined to make fun of celebrities who are trying to do some good, but we think it’s fine that Uma Thurman shills for [Tag Heuer] watches,” said David Rieff, author of A Bed for the Night: Humanitarianism in Crisis.

IN SUNDAY'S NEW YORK TIMES MAGAZINE, the Princeton philosopher Peter Singer takes a look at the philanthropic contributions of the nation’s mega-rich and calls on them, and the rest of us, to do more. For the most part, celebrities are not contributing significant portions of their private wealth to the causes they support. In Slate magazine’s list of the 60 largest charitable contributions of last year, only Oprah Winfrey, at No. 22, is what most of us would call a celebrity.

What celebrities contribute is, well, their celebrity, lending a public face to Parkinson’s (Michael J. Fox), animal rights (Pamela Anderson) or rainforests (Sting). They contribute their highly publicized good intentions. Whether good intentions always lead to good policies is another question.

In fact, many experts take issue with Mr. Sachs, the economist most likely to appear alongside Ms. Jolie or Bono, and his contention that Africa needs hundreds of billions in foreign investment to pull itself out of a “poverty trap.” In a recent book, Mr. Sachs’ nemesis, New York University economist William Easterly, shows that the $187 billion in foreign aid to 22 African countries from 1970-94 did “zero” to increase productivity. Other experts argue that reducing aid to many African countries would help fight the corruption and inefficiency that are the true causes of Africa’s impoverishment.

Take, for example, the event that arguably launched this new era of celebrity activism: Live Aid. In July 1985, British rocker Bob Geldof organized several concerts around the world that raised at least $100 million for famine relief in Ethiopia. But, as various journalists and scholars have since pointed out, Live Aid may have done more harm than good. While the aid distributed undoubtedly saved many, it was also complicit in dictator Mengistu Haile Mariam’s forced agricultural collectivization policy, a resettlement that may have cost as many as 100,000 lives.

For Mr. Geldof, “there was no political dimension to the famine,” Mr. Rieff wrote in Prospect, a British magazine. And herein lies the problem with much of the celebrity activism that has followed: its utter lack of, or even willful disdain for, political sophistication. (Issues that are obviously complex and controversial, such as the Israeli-Palestinian conflict, are avoided altogether.)

The recently leaked pitch for the rights to pictures of Mr. Pitt’s and Ms. Jolie’s new child included a shameless plug from Prof. Sachs, and everyone involved looked ridiculous. The purchasers were asked to “use them in a way that also draws attention to the needs of the Cambodian people.” To which Mr. Sachs added that the couple’s “vision and generosity will not only positively affect the lives of Cambodians today, it will also benefit generations to come” (according to Women’s Wear Daily). The pictures did nothing of the sort.

But now Mr. Pitt may be on to something. For his meeting with the climate scientists, sans Ms. Jolie, he was presented with an impressive packet of literature on the subject. Much of it was smart-layman’s material, such as Elizabeth Kolbert’s look at global warming in The New Yorker and top NASA climate scientist Jim Hansen’s survey of potential climate-change impacts in The New York Review of Books. But there was also meatier technical stuff. If Mr. Pitt reads it all, he will know more about climate change than the vast majority of Americans.

Surprisingly, there was no mention of the crash course in the tabloids, which at the time devoted much space to the premiere of Ms. Jolie’s new movie, The Good Shepherd. The Observer tried contacting Mr. Pitt through his publicist, who claimed not to have known about the briefing. And Erin Trowbridge, the Columbia spokeswoman who coordinated the event, said that neither Mr. Sachs nor anyone else would be available for comment. The meeting was “utterly confidential,” she said.

It’s sort of refreshing. Here’s hoping that next time Mr. Pitt speaks out, he’ll have something truly meaningful to say.

Consider the banality of modern-day evil: As Jeffrey Sachs reminds us in his new book, eight million impoverished men, women and children are condemned to death each year-not by terrorists or a modern-day Hitler or Stalin, but by you, the reader of this article, by me, and by every other literate and prosperous person in the West.

Our grandparents' generation used to assuage its guilt by making small offerings to reduce this toll, but accepted that global poverty was inescapable. By the mid-20th century, our parents' generation vaguely realized that extreme poverty could be ended, but was uncertain how. Today, says Mr. Sachs, we know how to end it; know which techniques to use and where to apply them; know how relatively little it will cost; and then choose-blindly, arrogantly, insouciantly-not to act.

That extraordinary indictment constitutes the heart and spine of Jeffrey Sachs' The End of Poverty-and controversy will rage over its accuracy and the author's prescriptions. Mr. Sachs, of course, is hardly new to this kind of attention. He made his reputation a quarter-century ago (among fellow economists, at least) by winning his Harvard tenure at 28, and has since become one of the most widely recognized economists of his generation, rivaled in terms of public recognition today only by Paul Krugman and Joseph Stiglitz. That celebrity status doesn't put him on the level of, say, an Adam Smith or a John Maynard Keynes-but it guarantees that he's talked about and looked to for advice and comment, much as John Kenneth Galbraith was a generation earlier.

Mr. Sachs is acutely aware of his celebrity-and while appearing to revel in it, seems to me intent on using it for far more important purposes than our Michael Jackson–Terri Schiavo–Martha Stewart–besotted culture is willing to accept.

U2's Bono wrote a vivid description of Mr. Sachs in the book's introduction: "His voice is louder than any amplified guitar … his passion operatic … physically very present, animated … with a wildness to the rhetoric but a rigor to the logic …. In time his autograph will be worth a lot more than mine." In the pages that follow, it quickly becomes clear that Mr. Sachs' proposals for ending global poverty (or radically reducing it) are interwoven with what amounts to an apologia pro vita mea. Whether this particular mix works-it produces a text at once autobiographical, technocratic and passionately moral-is an important but secondary question. (For those who know Mr. Sachs and development economics well, there are large and gnawing problems here.) The question the book itself asks is the one that really matters: Have we now reached a point in human history where we can in fact end poverty? And if so, will we?

The dream of ending poverty is as old as mankind itself, but only in the last two centuries, as powerful nation states and their variant nascent capitalisms together haltingly generated a new and largely stable prosperity in Europe and North America, has there been the remotest chance of success. And as we well know, battles over how the task should be accomplished have themselves consumed millions of lives and trillions of dollars.

Marx and his heirs had a memorable 150-year run, and various other political and economic ideologies-from fascism to religious utopianism-have no less claimed the abolition of poverty as their purpose. Following the collapse of the Berlin Wall, however, the terms of the game narrowed, as the North Atlantic bourgeois democracies have more or less inherited the field to themselves. Fifteen years ago, Francis Fukayama made his reputation by declaring this transitional moment "the end of history"-a far more sweeping claim than Mr. Sachs', and one to which (at least for the time being) Osama bin Laden has put the lie.

Mr. Sachs' vision, needless to say, is not original. John Maynard Keynes, in the depths of the Great Depression, fervently believed that the productive capacities that capitalism had unleashed in the 19th and early 20th centuries were, if properly managed by liberal democratic leaders (and skilled economic advisors), capable of putting "the hag-ridden" and "pseudo-moral" pursuit of wealth behind us. In 1958, Mr. Galbraith in The Affluent Society secured his reputation (and contributed a title to history) by arguing with great power and originality that the "ancient commonplace of poverty" was by then, at long last, behind us, at least in the West. The new order of the day, he said, was to solve the imbalance between the private market's cornucopia of goods and services and the relative "poverty" of public-sector goods and services, including universal health care, environmental protections, the creation of excellent schools, etc.

Mr. Galbraith spoke as a liberal, and his proud brand of liberalism dominated American domestic policy in the 1960's, as the New Frontier and the Great Society waged war on poverty and passed Medicare, landmark civil-rights legislation and landmark environmental protections. But liberalism's foreign policy-in Vietnam especially-proved toxic to its political agenda and power, at home and abroad. Following Richard Nixon's election in 1968-and then most clearly with Ronald Reagan's in 1980-public policy entered a new conservative ideological era. "Markets"-not government-were now meant to be the anointed agent of change ("government," Reagan told us, was "the problem, not the solution").

The West by then had been providing various forms of development aid to the Third World since the early 1950's, but out of motives as mixed as its "development assistance" in the preceding colonial era. By and large, liberals saw such aid as a moral and intellectual responsibility for reducing human suffering, while most conservatives viewed it as one more arrow in the West's anti-Communist quiver, designed to help fend off Marxism. The legislative result was a confused program of economic and military assistance, with decidedly uneven results-at worst shoring up (and lining the pockets of) repugnant dictators while not significantly reducing poverty.

In the 1980's, with the arrival of the market-knows-best era, the U.S., Britain, World Bank, I.M.F. and regional development agencies explicitly reconfigured the form, structure and rationale of their assistance. Described with disarming blandness as "structural adjustment" (or "the Washington Consensus"), the new strategy required Third World countries to assent to a list of tough "pro-market" conditions in exchange for Western cash: deregulation of domestic markets, fiscal balancing of state budgets, the sell-off of public-sector enterprises, free entry and exit rights for foreign capital, tight monetary policy, etc. If done, the West promised, a huge new flow of public and private capital would be forthcoming, and development would finally "take off."

The theory was blackboard-perfect, but proved disastrous in practice-so disastrous that by the mid-1990's, the World Bank and the I.M.F. explicitly abandoned "structural adjustment" for a new "poverty reduction" strategy. By then, however, Latin America's hugely unequal income and wealth distribution had grown dramatically worse, and African development had been set back by a decade or more. (As the old Soviet Union disintegrated, "structural adjustment" was nonetheless repackaged as "shock therapy"-and predictably produced similar results, with the state's vast wealth appropriated by billionaire oligarchs and the region's already-shabby living standards devastated.) Ironically, the 1980's and early 90's did see a major reduction in Third World poverty, but most of that thanks to extraordinary gains made by China and India, which had ignored "structural adjustment" advice.

This condensed history is germane to Mr. Sachs' book for two reasons: First, it contextualizes his proposals and, second, it shines a light on what stands in the way of their success. The so-called "Millennium Development Goals" at the heart of his book weren't originated by Mr. Sachs, but by deeply chastened economists and policy specialists working at the multilateral agencies which had once overseen "structural adjustment." The goals themselves were in fact put forward at the end of the 1990's, with a target of reducing global poverty by half by 2015. Today, in 2005, implementation is already behind schedule and growing worse day by day-and Mr. Sachs, who has joined forces with Kofi Annan and others to "relaunch" the M.D.G. campaign, have now reset the target date as 2025, in admission of what hasn't happened already.

The contribution of Mr. Sachs and his team has been to bring much more specificity to the goals, the costs, the relevant timelines and who in the rich West can foot the bill. By itself, this is admirable, because it puts the lie to those who've long said the M.D.G.'s were "utopian"-they clearly are not, by any reasonable measure. Thanks to Mr. Sachs, we now have the technocratic information, the blueprint for saving hundreds of millions of our fellow human beings first from insufferable deprivation and then from death.

The horrifying reality is that, by Mr. Sachs' calculations, America's share of the contributions needed to cut global poverty in half is a fraction of what the United States has so far spent in Iraq. Or, as he puts it slightly differently, the Bush administration's tax cuts this year will give more money to those earning over $500,000 than would be needed to meet our part in achieving the M.D.G.'s goals.

Yet the sheer, raw, unspeakable nakedness of those facts-and the reasons why they are true-also underscores the limits to Mr. Sachs' fundamentally technocratic arguments here. Visionary as they are, technically substantiated as they are, morally right as they are, they contain no real analysis of the concentration of power, the maldistribution of wealth, the diversionary mindlessness of our commercialized culture, or the feeble-mindedness of our politics today. At the very end of the book, Mr. Sachs rightly acknowledges these forces in our lives-but only to urge us to remember Martin Luther King, Gandhi and the abolitionists, all of whom achieved their dream.

The End of Poverty could contribute to opening up a new chapter in this troubled nation and this no-less-troubled world. For that, we should honor Jeffrey Sachs. Then others will have to take up the task of forging commitments, devising politics, driving and inspiring movements, and finally forcing systemic change in the way we live.

Richard Parker, who teaches at Harvard's Kennedy School of Government, is the author of John Kenneth Galbraith: His Life, His Politics, His Economics (Farrar, Straus and Giroux).

Mr. Bronfman's 31-foot-wide mansion, at 15 East 64th Street, sports a limestone façade on a block between Madison and Fifth avenues studded with similar opulent residences belonging to the likes of designer Donatella Versace, Sony chief Tommy Mottola, Donald-ex Ivana Trump and Mr. Wildenstein.

Mr. Bronfman, who serves on Vivendi's board of directors as vice chairman, bought his five-story residence in 1994 for $4.375 million, but he and his Venezuelan wife, Clarissa Alcock Bronfman, didn't move in until sweeping renovations were finished-five years later.

On move-in day, in September of 1999, Mr. Bronfman threw open the doors of his newly renovated mansion to The New York Times ' House & Home section, for an article that detailed extravagances like a sky-lit, two-and-a-half-story atrium court and a complex puzzle of hidden upstairs bedrooms.

"It's a very exciting renovation," said Larry Kaiser, president of Key Ventures Realty, who has been to parties at the house. "It's a lovely, beautiful, airy place that's young and open."

The Bronfmans had hired Canadian architect Peter Rose-who designed the Canadian Center for Architecture-to mastermind the townhouse's conversion from a nine-unit apartment building into a single-family townhouse.

Over the next five years, Mr. Rose gave the nearly 15,000-square-foot townhouse a neat divide between the lower three "public" floors-the living room, dining room and library-and the upper two "private" floors comprising the bedrooms-which, according to The New York Times , can only be reached "if you know which white panel is a secret door to a network of back stairs and hallways."

The day after the Times piece appeared, however, the New York Post reported that the article had angered Seagram shareholders, who watched their stock in the company drop 10 percent while Mr. Bronfman minced about those secret stairways.

This October, the 47-year-old Mr. Bronfman-by now Vivendi's vice chairman-told the Los Angeles Times : "My focus is entirely on trying to help all of the stakeholders, management and shareholders, to recapture the value that has been squandered and formulate a future that is exciting."

Mr. Bronfman will now have to widen that focus to include the search for a suitor for his $40 million trophy property. Though most brokers called the asking price excessive, they all admitted that the residence is an architectural masterpiece.

Just next-door to the Bronfman house, the townhouse that was once the locus of one of New York's most sensational divorce battles is going on the market for $35 million. International art dealer Alec Wildenstein is listing his family-owned townhouse at 11 East 64th Street-the residence in which he allegedly threatened his wife, Jocelyne, with a gun after she found him sharing his bed with another woman.

A judge barred Mr. Wildenstein from his home after the allegation was made, and the divorce saga that ensued spilled across the front pages of tabloids throughout much of 1997 and '98. The otherwise-private Wildenstein family-who are some of the most important art collectors and dealers in the world-had to wage a very public court battle to force Ms. Wildenstein to vacate the 64th Street townhouse, which she did in the spring of 1999, when a judge finally granted her a divorce on the grounds of sexual abandonment. She soon moved into a townhouse on East 82nd Street owned by Reagan White House veteran media advisor Fred Levinson.

Not that living arrangements in the house were ever typical. For years, Alec and Jocelyne Wildenstein occupied the third floor, and Alec's younger brother, Guy-president of Wildenstein & Co.-lived with his wife on the fourth floor, while the children of both couples were quartered on the fifth floor.

The Wildenstein family-whose patriarch, Daniel, died in 2001-owns four other properties on the block; the family's holdings were estimated in 1999 to total $5 billion.

The five-story, 29-foot-wide limestone townhouse at No. 11 East 64th Street is built out to the property line of the 100-foot lot, and with its basement and sub-basement, brokers estimated that the house offers 20,000 square feet. There's also a pool and an original winding staircase from the house's construction in the 19th century.

"It's one of the most incredible limestone mansions to come on the market in decades," said one broker who has toured the property.

Mr. Kaiser said the place felt a little dark when compared to the townhouse owned by Mr. Bronfman next-door.

Of course, one could always buy both and combine them. In fact, a buyer with $109 million on hand could buy three houses in a row on East 64th Street: Not only are the houses of Mr. Bronfman and Mr. Wildenstein for sale, but Mr. Wildenstein's neighbor, Sony head Tommy Mottola, is listing his condo-which occupies most of the townhouse at 9 East 64th Street-for $34 million.

midtown east

415 East 52nd Street

Two-bedroom, two-bathroom co-op.

Asking: $775,000. Selling: $775,000.

Maintenance: $1,164; 61 percent tax-deductible.

Time on the market: 45 days.

FIRST TIME'S A CHARM "I only had to show them this one apartment, and I thought they were all going to be easy like this," said Chris Seiden, a broker at Bellmarc Properties, of the gay couple she met at an open house-and who became the first clients in her new career as a Manhattan apartment broker. Her clients-one's a psychologist in private practice, the other does graphic design for a large financial institution-were checking out the place, too, and Ms. Seiden turned on the charm. "We're not going to get into a bidding war for this apartment, are we?" Ms. Seiden joked-mainly as a way of introducing herself as a real-estate agent. The maneuver worked, and Ms. Seiden got them interested in another place she had in mind. Apparently the mint-condition, 1,300-square-foot co-op on East 52nd Street was just what they had in mind, too-because Ms. Seiden had an accepted offer at the asking price in under a week. "I thought they would all fall out of trees like that," she said. "Life's gotten a lot more difficult since then." She's not the only broker saying that-though being new at the game might make it that much harder to take. "I had to show my second customer 12 apartments," Ms. Seiden said, "and I've shown my third customer 25 apartments-and we still don't have a deal."

turtle bay

845 United Nations Plaza (Trump World Tower)

Two-bedroom, two-and-a-half-bathroom condo

Asking: $2,266,800. Selling: $1,850,000.

Charges: $1,409. Taxes: $1,792.

Time on the market: 22 months.

DOCTOR IN THE HOUSE The young plastic surgeon who bought this sponsor unit at Trump World Tower got to know his broker by killing two of his other deals. The surgeon's cousin-a lawyer-had hired Insignia Douglas Elliman broker Dennis Mangone to find him and his wife an apartment on the Upper East Side. Each time the lawyer and his wife found a place they liked, they would call their cousin-the plastic surgeon-to give the final approval. "If [the couple] liked it, all of a sudden I would have to show it to all three of them the next time," said Mr. Mangone. After the plastic surgeon nixed two apartments his cousin and his wife seemed otherwise happy with, Mr. Mangone admitted to feeling "a little pissed off." But the plastic surgeon quickly ameliorated the situation. "Hey," he said, according to Mr. Mangone, "I'm looking for an apartment, too. Do you have something for me?" So Mr. Mangone invited both parties to check out some apartments at Trump World Tower. When they showed up, 14 family members had come along for the ride-and five of them were doctors. "There was an ear, nose and throat doctor, a podiatrist, an anesthesiologist, an ophthalmologist and a dentist," said Mr. Mangone. "We had to use two elevator cars to get them up to the apartments." This time, the extra vote-casters worked in Mr. Mangone's favor: The plastic surgeon and his cousin both found apartments they ended up buying. The plastic surgeon's new home has 2,000 square feet and north and east river views. "An adverse situation turned into a real happy ending," said Mr. Mangone.

TRIBECA

The Sachs Appeal: Columbia Buys $8 M. Townhouse for New Econ Star

Economist Jeffrey Sachs serves as an economic adviser to governments all over the world. But he couldn't protect his new employer, Columbia University, from a bidding war over an Upper West Side townhouse that drove the school to spend $8 million-$500,000 over the asking price-on the 20-foot-wide home. At $1,334 a square foot, that's the most expensive single-family townhouse in the history of the Upper West Side.

The townhouse will serve as a hospitality center for the world leaders who hang on Mr. Sachs' analyses, as well as a home for the professor and his family.

Columbia hired Mr. Sachs away from Harvard University in April to helm its new Earth Institute, an international-outreach program aimed at fostering collaboration between the university and global leaders. The university has reserved the ground floor of Mr. Sachs' new home-at 52 West 85th Street-as a permanent reception lounge for the Earth Institute's international visitors.

"It's a place where international dignitaries, donors and scholars will be received as a part of the university's growing global outreach," said university spokeswoman Lauren Marshall. "The house will be used to house scientists, economists and international leaders in government and business for dinners, receptions and informal discussions."

Ms. Marshall confirmed that Mr. Sachs-who is also a special adviser to U.N. Secretary General Kofi Annan-will be "paying rent, like all faculty do for university-owned housing."

Mr. Sachs declined to comment on the arrangement, but an administrator at the Earth Institute denied that Columbia bought the house as a way of sweetening the deal they were offering Mr. Sachs while he was still at Harvard.

"Long before they discussed details like that," said the Earth Institute's Mary Ellen Gallagher, "I know that Jeffrey Sachs said that he wanted the job. There was no 'Give me this or I'm not coming.' That's not the way the negotiations went."

Standing five stories tall and 20 by 55 feet, the 6,200-square-foot building is comparable to many in the neighborhood.

"That's 30 percent more than anyone has paid on the Upper West Side for a 20-footer," said Jed Garfield, a broker at Leslie J. Garfield & Co., one of the city's most respected townhouse-brokerage firms.

"It was identified as a strategic piece of real estate,"Ms. Marshall explained.

Prior to this sale, the most expensive townhouse purchases on the Upper West Side were a 30-foot-wide townhouse at 41 Riverside Drive that sold for $7.69 million in 2000, and a 23-foot-wide townhouse at 318 West 81st Street that closed for $6.75 million in 1999.

According to townhouse brokers, it simply looks as though Columbia signed the contract at what turned out to be the height of the market, in February.

"In retrospect, if you had to pick a date to sell your place, you would have picked February," said Daniel Douglas, one of the Corcoran Group's top West Side brokers.

According to city records, the house's previous owners bought it in 1997 for $1.67 million. Then they gut-renovated the place and put it back on the market in June for $7.2 million. At that point, Ms. Marshall said, a bidding war ensued, and the asking price rose to $7.5 million.

"Suddenly, people wanted a house in that area, and there wasn't anything else around," said Anne Snee, a townhouse broker and senior vice president at the Corcoran Group, who toured the property. "It's a beautiful house, and it was there in the right place and the right time."

The townhouse's gut renovation preserved some of the original woodwork; the first floor-the reception lounge-has a chef's kitchen and a south-facing garden. The upper four levels-the Sachs family residence-contain six bedrooms, a dumbwaiter elevator system and several wood-burning fireplaces.