Ed Viesturs is down $1,000, and he has only himself to blame. In 1997 Viesturs — arguably North America's premier high-altitude mountaineer — found himself slogging across climbing's largest stage for the ninth time. Joining him on the big E were four of the world's most experienced climbers, who by that point had tagged the roof of the world a total of 14 times. This time, however, the thrill was gone.

"It was a hot day, and we were bored and decided that we'd had enough of this mountain," recalls Viesturs, 45, over drinks at the Hotel Yak & Yeti in Kathmandu, Nepal. "We vowed that day never to come back." And just like that Everest Anonymous, climbing's own 12-step program, was born.

The pact they made carried stiff penalties. Should any of them set so much as a crampon into the Khumbu Icefall, the glaciated gateway to Everest, a payout of $1,000 would be required to each member who remained on the wagon.

But temptation would overcome solidarity. This spring Viesturs and three other Everest Anonymous members had returned to the peak and had to shell out a grand to the remaining holdout, New Zealander Guy Cotter.

Viesturs and his associates are among thousands of sea-level averse souls afflicted by a compulsion for high-altitude adventure. And not just Everest (though that works for a quick fix). The bug is so hard to resist that a growing number of climbers are determined to top the highest peak on each continent — dubbed the Seven Summits. Beyond that, some seek a higher thrill still — the ultimate in alpine summitry — scaling the 14 highest mountains, those taller than 8,000 meters, or 26,250 feet.

Call it serial summit disorder, a habit bordering on obsessive hand-washing. And it is driving a wedge between purists, out for the challenge, and those who are looking for a little more gain — say, bragging rights, fame and marketing dollars.

Adventurers now compete for the title of the youngest, oldest or the first of their nationality to climb the Seven Summits, which comprise Everest, Aconcagua (South America), Denali (North America), El'brus (Europe), Kilimanjaro (Africa), Kosciuszko (Australia) and Vinson Massif (Antarctica).

Some veteran climbers say that the growing mania for records and serial peaks has elevated quantity over quality, with the climbing lost in a stampede for payoffs beyond the summit. They deride the increasing number of woefully inexperienced wannabes as trophy hunters.

"It's kind of degrading the process of mountaineering," says Viesturs, who lives in Bainbridge Island, Wash. "If I'm taking somebody [to Everest], I want somebody who loves to go climbing, not just wants to say they climbed Everest."

Yet more and more prize hunters are happy to boast their way to lucrative book deals, launch television programs, land corporate sponsorship deals and even secure a much-coveted spot on the motivational speaking circuit, for fees that can run to $10,000 a lecture.

Changing priorities

Climbers a century ago had a globeful of far-flung, virgin summits for the pickings. The contest wasn't about bagging peaks but about facing an unknown, frozen monolith of ice and stone in gear little removed from streetwear.

But as summits were discovered and claimed, a new gauge of climbing prowess emerged. The emphasis was on numbers and results, not on the process. It began with Texas millionaire Dick Bass. The owner of Snowbird Ski & Summer Resort in Utah, Bass kicked off the serial peak phenomenon when he became the first person to climb the Seven Summits (partner Frank Wells completed six). He was guided up the routes by David Breashears, credited with opening the floodgates to Everest after guiding Bass to its top in 1985 — and a founding member of Everest Anonymous.

Bass, who declined to comment for this article, told Forbes columnist Jim Clash, author of "To the Limits," that he "got into the Seven Summits because it was a challenge. I've been successful in business. If that's all I was chasing, it would be an empty bauble of accomplishment. I know a lot of executives who wake up and say, 'My God, there's got to be more.' That's why they want to climb mountains at an older age. They want to win the self-respect that comes from doing something that really lays it on the line."

Bass' summit binge seems to have married the entrepreneurial impulse, in which fierce achievement and quantifiable results meet, with the traditional sensation-seeking side of climbing, leading to marketing-related climbers such as Annabelle Bond, a sassy British amateur climber currently trying to parlay her Seven Summit success into an adventure TV show.

Career paths aside, chief among climbers' motivators is a craving for sensation, says psychologist Christopher Cronin, author of the study "Sensation Seeking Among Mountain Climbers." Some people crave higher doses of stimulation than others, and as they indulge thrill-seeking behavior, they can be conditioned to want more, he says. These folks can't help it. They're just doing what their biochemistry tells them.

High sensation-seekers such as climbers lust after the thrills and achievement that come from risk-taking, but, most particularly, for their biochemical payoff: dopamine, a chemical that stimulates pleasure centers in the brain. Besides the chemical charge, the "flow" experience identified by social psychologist Mihaly Csikszentmihalyi also kicks in, and the climber enters a zone of such concentrated engagement that all other concerns and distractions are screened out.

But the fire that fuels compulsive summiteers can be so insistent that it can burn climbers and those around them. Maria Coffey lost her boyfriend, British climber Joe Tasker, who disappeared without a trace on Everest.

"When the news came through that he had disappeared, my life was shot to pieces," says Coffey, author of "Where the Mountain Casts Its Shadow." "There were high costs even when he was alive. Each time he left on an expedition I was paralyzed with fear."