Unless it's a gala movie premiere in Cannes, Venice or L.A., Brad Pitt doesn't normally show up in a suit. Usually the celebrity superstar -- one half of the duo known globally as Brangelina -- is snapped in torn jeans and a scruffy T-shirt, hair askew.

But the 42-year-old actor was all spit and polish at a private brunch in Toronto yesterday, clad in a black jacket and pants, crisp white shirt and tie. The designer attire was out of respect for a man of whom few tabloid readers would ever have heard.

Mr. Pitt -- who didn't attend former U.S. president Bill Clinton's star-studded birthday bash Saturday night at the Fairmont Royal York hotel -- came to pay tribute to Jeffrey Sachs, a gregarious but humble economist from New York who heads up the UN Millennium Project.

Mr. Sachs, a man known worldwide as one of the foremost experts on poverty, was feted last night at the swank Carlu by Oscar-winning actor Matt Damon and Ocean's 11, 12 and 13 chum Mr. Pitt at the hot-ticket fundraiser One X One, set up last year to improve the lives of children around the globe.

At noon, Mr. Pitt surprised guests in the lobby of the Fairmont Royal York when he sauntered through, surrounded by beady-eyed security guards wired up like Christmas trees. He walked into the Library Bar and immediately started working the room, shaking hands and chatting amiably with the 50 or so assembled guests invited to a private brunch by Liberal MP Belinda Stronach and One X One founder Joelle Adler, president of Montreal clothing company Diesel Canada.

"I could have gone home last night," explained Mr. Pitt, resting his lean form against the dark panelled wall, while sipping red wine. "But I wanted to stay to meet and support Jeff." (Mr. Pitt walked the red carpet Saturday night for the premiere of the acclaimed film Babel. Partner Angelina Jolie was not on hand.)

"Angie is really the driving force in this work," Mr. Pitt said yesterday. "But we are trying to set up a village in Cambodia, and I wanted to spend some time with Jeff picking his brain."

By "village," Mr. Pitt is referring to one of Mr. Sachs's pet projects: the Millennium Villages, which have been developed by a team of scientific experts at the Earth Institute at Columbia University (where Mr. Sachs is director) to help the poorest of the poor by investing in health, food production, education, access to clean water and essential infrastructure. The first went up in Sauri, in western Kenya, in June of 2004. Today, there are 12 sites in 10 countries, with a goal of establishing 100 by 2009.

Yesterday, after Mr. Pitt and his tablemates (Ms. Stronach, her 14-year-old son Frank, NHL tough guy Tie Domi and Rogers Media scion Edward Rogers Jr. and his wife Suzanne) polished off beet carpaccio and wild salmon, it was announced that Mr. Rogers (Ted's only son) and his wife would be donating $1.5-million (U.S.) -- in partnership with One X One -- to start Canada's first Millennium Village.

After the meal, Mr. Pitt explained to many gathered in the crowd that he and Ms. Jolie -- who have an adopted child from Cambodia -- plan to leave soon to begin the groundwork for a Millennium Village in that country.

After the brunch, the actor spent another hour in an empty ballroom at the hotel with Mr. Sachs and his doctor wife, Sonia, discussing the concept behind these villages. "The bottom line is the solutions are simple," Mr. Sachs said, adding what is needed is basic support for self-sufficiency, such as bed nets, vaccines for malaria, school lunches and wells.

Ms. Jolie and Mr. Pitt have three children, Maddox, 5, Zahara, 1, and newborn Shiloh. Ms. Jolie is a long-time friend and supporter of Mr. Sachs, who wrote the landmark book The End of Poverty: Economic Possibilities for Our Time.

Not long ago, the two paired up to do an MTV documentary called The Diary of Angelina Jolie and Dr. Jeffrey Sachs in Africa, which offers actual solutions to famine, plague and conflict.

In line with the commitment to changing stereotypes and stagnant mindsets, Mr. Pitt also recently told Esquire magazine (in the October issue) that "Angie and I will consider tying the knot when everyone else in the country who wants to be married is legally able."

Earlier Sunday morning, Mr. Damon and his filmmaking partners, Marc Joubert and Larry Tanz (pals from Boston), talked about their new $2-million (U.S.) documentary Running the Sahara, about three men (including Ottawa's Ray Zahab) who run the equivalent of two marathons a day, for roughly 75 days. Their motivation for crossing the Sahara is to raise awareness of the country's plight and indomitable spirit. It will be directed by Academy Award winner James Moll (The Last Days).

Mr. Damon also announced he and his friends are establishing a fund called Africa H2O that will be dedicated to providing poverty-stricken villages with wells and clean water.

"A child dies every 15 seconds in the world because they don't have access to clean water," Mr. Damon said. "It's truly mind-boggling, and outrageous, and unnecessary. But beyond the issue of just surviving, it's the whole issue of the quality of someone's life."

At 6:30 last night, Mr. Pitt met Mr. Sachs on the red carpet leading into One X One's bash at the Carlu.

Later at the event, which drew more than 500 people, Mr. Pitt told The Globe's Johanna Schneller that he is "thrilled" to be a father, but he is not one of those parents who gets too anxious.

"I'm just happy to be along for the ride," he said. "It's just amazing to see who they are, see their personalities and just watch a human being grow up close."

Singers John Legend, Chantal Kreviazuk and Raine Maida (Our Lady Peace) performed.

Mr. Pitt and Mr. Damon's star power at the fledgling One X One event put the charity firmly on the map. Last year, founder Ms. Adler raised $1.3-million. This year, she's on target to bump that up considerably. However, she declined to give a dollar figure until the final tally could be completed at the end of the night.