There's some debate whether Mark Twain, George Bernard Shaw or somebody else said, "It's a pity that youth is wasted on the young." But it wouldn't surprise me if it were someone in the fashion business who coined the phrase.

Fashion week in New York, Milan or Paris is often an exercise in wasted youth. Teenage models play dress-up on the runway, trying to look grown-up in clothes meant for real women. Snarly fashion assistants just out of college who have a sense of self-importance that far outweighs their job title take great delight in giving attitude to anyone they deem less notable. Botoxed fashion editors in stilettos and miniskirts on the front row strain to look young and hip.

So it's a delight to see an elderly-but-still-going-strong American fashion original finally get his due.

At 82, Bill Cunningham continues to be a front row fixture in all the fashion capitals as well as on the streets of New York. Dressed in a blue smock like the kind Paris sanitation workers wear and with his camera always on hand, he chronicles fashion trends for The New York Times. His Sunday photo spreads on the street scene and society parties have appeared in the paper of record since the 1970s and provide an incomparable history of fashion.

Cunningham's life and dedication to fashion is chronicled in a fascinating new documentary, Bill Cunningham New York, at the Museum of Fine Arts Friday night (at 7 and 8:45 p.m.). I saw it with a nearly packed house last weekend at the museum and everyone in the audience was charmed by Cunningham's spirit, dedication to his craft and stellar work that transcends who-wore-what to capture important moments in time.

Even an influential fashion editor like Vogue's Anna WIntour worries when Cunningham doesn't take her photo; when his camera stays down, it's his tacit disapproval that what she's wearing isn't interesting enough to catch his eye. "I've said it many times, we all get dressed for Bill," she says in the movie.

In a world of rampant materialism, Cunningham is downright frugal. He doesn't own a car or take taxis; instead he bicycles to events all over Manhattan in one night — on his 29th bicycle. The other 28 have been stolen over the years.

He doesn't take freebies of any kind: in fact, he won't even eat or drink anything at a society event. "I eat with my eyes," he tells an organizer who begs him to dine at a high-society gala.

Before being forced to move into a new apartment last year, he lived in a hovel above Carnegie Hall with nothing but a small bed and dozens of filing cabinets to store his negatives because he doesn't believe in digital photographs. He shared a bathroom in the hallway with other tenants and never used his kitchen.

"Who the hell wants a kitchen and bathroom?" he says while looking for a new apartment. "It's more rooms to clean."

He loves to shoot on the street in all kinds of weather, getting some of his best, most candid photos when it snows and pedestrians let their fashion guard down. "I let the streets speak to me," he says. "You have to stay on the street and let it tell you. There are no short cuts, believe me."

In inclement weather, he wears a cheap plastic poncho. When it rips, instead of buying a new poncho, he repairs the old one with duct tape. "It's going to tear anyway," he explains.

He might come across as an oddball, but he's anything but that. His pure, unadulturated love for fashion motivates him — and nothing else.

"It's the armour to survive the reality of everyday life," he explains at one point in the movie. "You can't do away with it. It would be like doing away with civilization."

The high point in the movie for me comes when he is presented the Chevalier of the Order of Arts and Letters from the French minister of culture in Paris during the fall of 2008. I was fortunate to be there to see Cunningham and longtime fashion writer Marylou Luther receive the honor from French officials at the Musee des Arts Decoratifs. I try to sit next to Luther whenever possible at shows because she has an encyclopedic knowledge of fashion history, having viewed Yves Saint Laurent's first collection for Christian Dior in 1958 among other career highlights.

As the movie shows, the night was especially moving as Cunningham, using a combination of French and English, explained the importance of fashion.

At the end of his short speech, Cunningham was so moved with emotion that he burst into tears. It was an electric moment.

Then he was back to doing what he does best. He had his camera with him, and throughout the evening he photographed the surroundings.

"So you're working at your own party?" one woman asked him.

"It's not work," he said, "it's pleasure."