Karen Heimdahl used to be part of the throngs that crowd area malls at Christmas. But this year, bound by the Compact -- a growing social movement in which members vow to buy nothing new for a year -- she hit used book stores and consignment shops. Last Christmas her husband received gadgets from Best Buy. This year he unwrapped a hand-powered coffee grinder that Karen scoured eight antique stores to find.

"Buying new is so much easier," she lamented.

The American economy depends on consumers willing to buy the latest in fashions, furnishings and flat-screen TVs. Indeed, in the weeks after Sept. 11, 2001, shopping was cast as a patriotic duty, a way to help prevent the economy from tipping into a recession.

But the Compact, started by a group of San Francisco friends as a rebellion against what they see as gluttonous consumerism and its thoughtless destruction of the environment, turns that notion on its head.

Today, with a former vice president as the spokesman for global warming and higher energy prices hitting everyone's pocketbook, some Americans see going green as their new duty, or at the least, a money-saving measure. More mainstream Americans are going beyond recycling to considering their carbon footprint when flying, buying locally and second-hand shopping as an environmental statement.

A KPMG Consumer Survey conducted in December found 88 percent of respondents were very concerned about the environment.

For others, buying less is the harsh reality after years of relying on stock market gains and home appreciation to live beyond their paychecks. With talk of a possible recession, others are spending less to fluff up their cash cushion.

The Compact, named after the creed made by the revolutionaries who sailed here on the Mayflower, started in 2004 with a San Francisco dinner party. The conversation had turned to the downsides of recycling, and the group agreed to a revolutionary idea of its own: to buy nothing new, aside from a small list of exceptions that includes medicine, underwear and cleaning products. They could buy food without restrictions, including eating out.

Officially the Compact has grown from 10 friends around the dinner table to more than 8,700 members of online users groups today. Founding member John Perry figures thousands more are living the Compact life offline, though it's hard to track exact numbers of members and success rates.

"We never set out to start a movement," says Perry, who works in the high-tech industry. A 2006 story by a San Francisco Chronicle reporter, who was a friend of a friend of a Compact member, changed that. The story created buzz around the world. There are about 50 users groups on Yahoo from as far away as Thailand and Australia. One in Minnesota was formed last January and has 41 members, although it's somewhat inactive.

Candles for dad

It was fall of 2006 and Heimdahl was counseling a growing number of Minnesotans having trouble paying their mortgage and credit card debt when she read about the Compact in the news.

"For a while I had been feeling fed up about the consumer nature of our society," said the 31-year-old financial counselor for Lutheran Social Service. "I think part of it is what I do for my job too, seeing a lot of people have debt ... and not having anything to account for it."

Still, she didn't sign up right away. "My first thought was 'well, I don't need to do that, I don't buy much stuff anyway.' But then I realized that was an excuse."

On April 8, 2007, she and her husband were sitting at their desks in their Waconia home. Without a triggering event or much thought of how this would change her life, she signed up for the Compact group online. Although her husband, Andy, was just feet away, she didn't mention her new commitment until later that day. She worried about his reaction, knowing he viewed the Compact as extreme. But he surprised her. "He was actually very supportive."

"I wasn't sure she was going to be able to follow through," said Andy, 33. "In this consumer-driven society it seemed like a nearly impossible task."

It hasn't been easy. The week after she signed up, she picked up a box of candles for her father's birthday party. Driving to the party with her sister, she confessed her sin, which her sister brushed off. It was months before Heimdahl set foot in a big-box store again.

"Every three months is when I tend to have a cheat," she says. After the candles was the gift certificate she bought for a new motorcycle windshield for her husband. She didn't actually buy the item for him, but with the gift certificate, "the intent was there."

Then in September, an out-of-town friend had a baby. The new parents were hosting the Heimdahls and they wanted to show their appreciation. They purchased some wine for their friends, within the guidelines of the Compact. It was the newborn gift that forced Karen to break the rules. "I looked and looked and couldn't find anything [used] and I found this outfit and it was so cute and I caved. I regretted it, but not really," she said. That was her last new purchase. "Maybe I'm getting better."

Repulsed by the dollar bins

Her dedication has impressed her friends and family. Some have said they've made small changes -- like saying no to plastic bags or thinking twice about buying something they wanted but didn't need.

Andy Heimdahl, despite his initial skepticism, has also been living in the Compact spirit, fixing a wheelbarrow instead of buying a new one and making a coffee table for his wife for Christmas.

Heimdahl has changed too. "It's really taught me patience," she said. "Solutions will come if I wait." She found buttons needed for a sweater she knitted at an antique store. She spent more hours searching for the materials to make a compost bin than she cares to remember. She's also learned to garden and cook her bounty. "It's kind of forced me to slow down in some ways, which I really like."

And there's the financial benefit of not spending $10 here and $50 there. The couple retired a loan for their property up north and have more money in savings. "Our pocketbook really looks much better for it," said Andy.

During her time, she's tried not to keep a list of new items she wants, although the first snowfall renewed her desire for new skis and she'd love to get a cold press coffee mug before she and Andy go camping again in the Boundary Waters.

Heimdahl can buy both on April 9, when her Compact ends, but "I'm not going to go out on a shopping spree," she says. And the influence the Compact has had on her habits is here to stay. "Everyone can make minor changes with just a little shift in mentality," says Heimdahl. She used to love Target and enjoyed wandering through the store's abundance of cheap, trendy items. Now a walk by the dollar bins repulses her. "There's all this stuff and so much is unnecessary and disposable."

Kara McGuire • 612-673-7293