The young pigs scurried on stubby legs into the field, tumbling into one another and racing onward like an army of squat, exuberant soldiers. Paul Willis, finishing his chore of shunting four others onto a trailer for a trip to the slaughterhouse, looked on in satisfaction.

"We're working with nature," said Willis, a self-described hog farming crusader, "allowing the animals to explore and rut and run around, to let a sow build a nest. That's all a part of what a pig is."

The work of Willis and a growing legion of small-scale farmers is helping to change the way pork is produced, and the way it is perceived. After years in the hinterlands of American culture, when declining demand and profits drove away hundreds of thousands of farmers, pork is becoming cool again.

And some of the farmers who survived are making a whole lot of money.

Jon Caspers, based up the road in Swaledale, produces pork on a grander scale, using efficient techniques Willis disdains. He drives to a long, low building where hundreds of pink pigs are housed, fed and watered in indoor pens until they are ready for the knife. Casper's pigs are bred lean and marketed as "the other white meat," in tune with the demands of the anti-cholesterol market.

"We've been through an awful long dry spell. It's finally been a lot better this year," said Caspers, past president of the National Pork Producers Council. He joked that some producers are "making money for the first time in I don't know how long, and they don't know how to act."

There are many factors in pork's sudden profitability. The industry is following in the hoof prints of the beef business, which benefited enormously from the protein-rich Atkins and South Beach diets and the message that eating good meat isn't always a bad thing. Pork is also benefiting from being marketed as a cheaper alternative to hungrily devoured, and increasingly pricey, steaks and roasts.

Also, exports are up more than 20 percent this year alone, and feed prices are down because of the nation's second consecutive huge harvest. But analysts say there is something intangible in pork's rise, something that can't be explained in a chart.

Keith J. Collins, chief economist at the U.S. Department of Agriculture, said U.S. producers are likely to sell $15.1 billion worth of hogs this year, compared with $10.6 billion in 2003. He ran down a list of facts and figures about pork prices and yields, then paused. "I'm being almost a non-economist here," he said, "but it's very hard to be looking at how you can kill 2 million hogs a week and still be looking at prices above $50 per hundredweight."

Collins feels certain that demand built on improved taste has something to do with the gains. "I remember 10 years ago when you'd buy a pork chop and there was nothing you could do except cook it for two hours," Collins said. "Over a period of time, the quality of pork has changed."

The November issue of Food & Wine reports that "American cooks are becoming pork obsessed" and declares in an eight-page spread that "all signs point to a major renaissance." Or take it from Eric Ziebold, one of the country's hottest chefs -- and an Iowa-raised pork lover. He recently opened CityZen in Washington after eight years at the French Laundry in California's Napa Valley.

"The meat industry has come up with something special in the last few years," Ziebold said. "Now we're getting to a point where people are noticing the difference and paying the difference. The price of the meat has gone up considerably, but the quality has gone up exponentially."

Chefs love pork's versatility, Ziebold said, an observation confirmed by a survey of menus across the country that feature dishes from maple-glazed chops to cured cheek and the current rage, pork belly, which is bacon that has not been brined or cured. As Ziebold put it: "It's meaty pork that's very, very tender but very, very crisp. What's not to like?"

Ziebold, cheering most recently about shoats, small pigs usually younger than one year, credits diners who are "getting over the health hype" -- words that would make a cardiologist shudder -- and small-scale farmers who are "reintroducing a more artisanal product."

The artisanal product would be pigs such as those raised by Willis and the 430 farmers he has recruited for the Niman Ranch Pork Co. from 12 states -- 10 in the Midwest, plus Virginia and North Carolina. His business, which he sometimes calls "free-range pigs," started 10 years ago and is growing by about 20 percent a year.

Whole Foods Market is a major customer. Others are Chipotle Mexican Grill, owned by McDonald's, and upscale restaurants.

Niman farmers are bringing back hardy breeds of hog, which they let run and root outdoors. This avoids confinement and antibiotics alike.

Boosters argue that fatter and moderately muscled pigs make tastier dishes. What Willis calls an "industrial pig" is bred to be what the business calls 56 percent lean, whereas Niman favors 48 to 51 percent lean.

Then there's the happiness factor. It may be a taste component that cannot be proved, but Willis swears by it.

"A pig likes nothing better than a 20-degree day in winter, when it's sunny and they can play in the snow," said Willis, once a poor farmer who considers his work a crusade against the "industrial paradigm." He has an endorsement from the Animal Welfare Institute and tries to recruit like-minded farmers, including those who surrendered to the market but want another chance.

"We're not pork producers. We're hog farmers," Willis said. "We're marketing two things. We're marketing an opportunity for farmers, and we're marketing pork to consumers. Maybe we can do a small part in renewing the countryside."

Chipotle developed an ad campaign around the concept, with one poster that announces from Thornton, "Welcome to Porkutopia," and another that says, "For pigs, it's the good life. . . . Try the pork in your burrito, taco or bol. It may just be the nicest meal this side of Thornton, Iowa."

Artisanal pork. Pastured pork. Free-range pork. Natural pork. All are names for the work Willis and a growing number of similar farm operations across the country are performing. Another term for it is "niche pork," signifying the limits of the sector's reach. Yet it may be that the high-end hogs are influencing consumer tastes just as human dietary preferences are breaking with recent patterns.

"It has been a remarkable yield for pork demand. It's the perfect storm," said Steve Meyer, an Iowa consultant and former chief economist at the National Pork Board. He said avian flu in Asia and scattered bans on imported beef helped the U.S. industry, and that Atkins "gave permission to those who weren't on the diet to eat more meat."

Yet Meyer is another economist fascinated by the pork phenomenon who found himself exploring nonstatistical explanations.

"I have zero evidence, but I think after September 11 there was a degree of fatalism that entered American thinking," Meyer said. "Some of us said life's too short to eat tofu and greens. Life's too short, and I want a steak."

Paul Willis, right, and business partner Jon Carlson raise hogs in Thornton, Iowa, that spend much of their lives outdoors and are not given antibiotics.For Paul Willis, letting hardy pigs "explore and rut and run around" is a blow against the "industrial paradigm."