Portland, Ore. —- It's been 20 years since ad man Dan Wieden came up with the phrase "Do It," attached "Just" to the front and pitched the tagline to lukewarm reception from Nike executives on the losing side of a shoe war with Reebok.

Today, the eight-letter phrase is among the two or three slogans rated most memorable in advertising history, and Nike is the world's largest sporting goods maker.

The company, of course, is exploiting the anniversary of "Just Do It" to launch a worldwide marketing campaign for the Olympics in August. Its online component and international rollout this past weekend show how Nike's $18.5 billion business and marketing strategy have changed since 1988, when Reebok surpassed its $877 million in sales.

Wieden, co-founder of the Portland ad firm Wieden + Kennedy, penned "Do It" as a sort of "connective device" that evoked an athlete's transformation to a great competitor. Later, he added another word for emphasis.

"We're usually not big ones for taglines," Wieden said in an interview in 1989. "But because we were doing so many spots and the look had to be different, we felt we needed to have some cement to the thing. We felt 'Just Do It' would work for those at the competitive level as well as for people interested only in fitness."

It did exactly that, experts say, and more.

From a marketer's perspective, the line was gold. It summed up Nike's image concisely and memorably for consumers. And it drew lasting admiration from marketing experts.

"It was quick, easy, cocky, to the point and a bit irreverent, all of which Nike is," said Peter Moore, who designed the Air Jordan logo for Nike and later headed up Adidas' North American operations.

"It's an immediate call to action with no thinking involved," said Jill Mosteller, assistant marketing professor at Portland State University.

The slogan also spoke to everyone who has ever procrastinated about exercising, said Bill Borders, co-founder of the ad agency Borders, Perrin and Norrander.

"It is essentially a time-worn expression that had been around for ages," Borders said. "But it lifts that phrase out of common usage and breathes new life into it.

"Not bad for eight letters."

"Just Do It" slips off the tongue with ease and, therefore, easily lodges in our brains, said Steve Cone, author of the new book "Powerlines: Words That Sell Brands, Grip Fans and Sometimes Change History."

Unlike many companies, Nike has deployed its slogan consistently and effectively across many media, without altering it, Cone said.

"To be effective, a tagline should project personality and attitude," said Cone, chief marking officer for Epsilon, a marketing services firm. "Nike's line does that in spades. Most lines today do not."

Wieden has said in past interviews that neither Nike executives nor the public immediately embraced the line.

But news coverage shows it didn't take long.

Coming off a successful "Revolution" ad campaign, the first "Just Do It" spot featured 80-year-old distance runner Walt Stack and debuted July 1, 1988.

Subsequent TV and print ads used clever lines, catchy music and multisport athlete Bo Jackson's "Bo Knows" chutzpa. By 1990, the agency had harvested a key industry award in New York.

People wrote to Nike saying "Just Do It" had inspired them to leave abusive husbands and achieve heroic feats.

By 1998, Nike's global sales had ballooned to $9.2 billion. Its share of the U.S. athletic shoe market jumped from 18 percent to 43 percent, according to the Center for Applied Research, and it remains dominant today.

In 1999, Advertising Age ranked the phrase No. 2 in its survey of the most memorable slogans of the 20th Century —- behind De Beers' "Diamonds are forever."

Taglines are tricky, Borders said.

As Nike unveiled the initial $20 million "Just Do It" drive, Borders' firm was launching a $30 million campaign for underdog shoemaker Avia. Its tagline: "For Athletic Use Only," concocted after research showed 80 percent of consumers weren't using the shoes for sports.

"The challenge is to capture as briefly as possible the essence of a brand promise," Borders said, "and to do it in a way that hasn't been done, will be readily recalled and —- ideally —- be picked up by everyone and played back in everyday parlance. Not so easy."

BEST SLOGANS

Results of Advertising Age magazine's 1999 survey of the 10 best ad slogans of the 20th century:

1. Diamonds are forever (De Beers)

2. Just do it (Nike)

3. The pause that refreshes (Coca-Cola)

4. Tastes great, less filling (Miller Lite)

5. We try harder (Avis)

6. Good to the last drop (Maxwell House)

7. Breakfast of champions (Wheaties)

8. Does she ... or doesn't she? (Clairol)

9. When it rains it pours (Morton Salt)

10. Where's the beef? (Wendy's)

Source: Advertising Age