GENESIS: The original premise of ESPN's "This Is SportsCenter" ads, launched in 1995, was that the network's Bristol, Conn., offices were the center of the sports universe—a fantasy world where athletes and mascots lived and worked together with anchors and journalists. The conceit arrived fully formed. Aside from the specific athletes and plot lines, Wieden + Kennedy New York has changed next to nothing in the almost 400 spots since. The campaign's style, and even its name, were inspired by This Is Spinal Tap, the rock mockumentary from a decade earlier. While Nike and every other sports marketer portrayed athletes as superhuman, ESPN presented them as absurdly yet relatably human—doing menial tasks, chatting with co-workers, enduring office life's endless small humiliations. By bringing them down to size, in a way sports fans loved, ESPN built a larger-than-life campaign that athletes now practically beg to be involved in. "It's not hard to get almost any athlete we want, because the writing is so good, the campaign is so beloved," said Seth Ader, ESPN's senior director of marketing. "We struck on a nice formula, and just kept it going." After 17 years, it shows no sign of slowing down.

COPYWRITING: The writers work off topical stories and the athletes' personas. One of W+K's favorite spots, "The Kid" (1996), shows a teen drafted out of high school to be an ESPN anchor. He's a bust, just as so many teens in the NBA were at the time. Another favorite, "Musical Chairs" (2009), shows the signature office humor, as LeBron James finds his office chair—a huge throne—stolen by anchor Scott Van Pelt, who humorously denies it. "Not everything can be a big set piece where something crazy happens. It has to be smaller and more believable," said W+K creative director Brandon Henderson. "It's the exact opposite of any Nike or Reebok commercial with these athletes, where they're always at the peak of their performance and they're doing things that are unbelievable. In these commercials they're making coffee or trying to unjam a printer." An exception is a third favorite, "Spy" (2011), in which NHL star Alexander Ovechkin, while doing some filing, is jokingly accused of being a Russian spy—then it turns out he actually is.

The spots tend to stick to the scripts, though the team will improvise if things aren't going well. The biggest challenge is not repeating jokes. "So much has been covered, and covered well," said Henderson. "If you're thinking of a joke for a quarterback, and there's not something super specific about the quarterback you're writing for, you have an uphill battle. A lot of scripts hit the floor unless they get into something that's not been done. And then from there it has to reach that level where you want to tag it with 'This Is SportsCenter' and put it out in the world."

Ader said his favorite spots are the ones with no edits—the spots that are just one continuous 30-second take. "That's sort of the true documentary or mockumentary style," he said. "Those are the hardest to shoot because they have to time out perfectly, and the performances have to be perfect. But to me, they feel like the purest and best of the spots." While the writers feel pressure to live up to the campaign, the volume of spots eases the burden on each one. "You feel like you can take some chances, and maybe make a quieter spot," Henderson said. "Like the Oregon duck looking out the window—on paper, that's a spot you're probably not itching to do. But when you see the results, it's unbelievable."

ART DIRECTION/FILMING: The ads are shot in Bristol during the workday, with minimal set dressing. Most of the extras are just ESPN employees doing their job. The cubes are made to look lived in, with athletes' family photos and a few flourishes. (Brian Wilson had beard dye on his desk.) The athletes are always in uniform, which helps identify them but also adds to the comic pathos—i.e., they're dressed for the wrong job. The agency films seven or eight spots on two-day shoots several times a year. Almost all of them are directed by David Shane of O Positive.

TALENT: "We had one NFL quarterback tell us that being in a SportsCenter spot is on his bucket list," said Ader. The anchors, though less giddy, are good sports, too—given some unglamorous plot lines. "We'll have them put on a skin-tight Captain America outfit and run around with a shield, and they'll do it. Sometimes reluctantly, but they'll do it," said W+K creative director Stuart Jennings.

The athletes aren't paid, said Ader, but can have $1,000 donated to charity in their name. There's no ideal ratio of female-to-male athletes—it just depends on who is popular or newsworthy at any given moment. A decade ago, W+K would just write the funniest scripts and then cold-call the athletes, resulting in a pretty low success rate. The agency has learned to look much more closely at schedules and seasons and availabilities—and now plans special ads ahead of marquee events like the Olympics. The most notable athlete who's never appeared in a SportsCenter ad is Michael Jordan, though both agency and client say they haven't asked him in a long time. "We may have missed the boat on that one," said Jennings.

SOUND: It's mostly ambient noise. "I think we've used the same office-phone track for the whole [time]," Jennings said.

MEDIA: The ads air only on ESPN's properties. "They're a treat for our viewers to stay tuned during the commercials," said Ader. And with sports always evolving, the spots should continue indefinitely. "The campaign really is our way of providing light commentary on the world of sports and the athletes who dominate it," Ader said. "Creatively, it's really endless. There's no end to where this campaign can go." Added Henderson: "It mirrors the sports world. As long as sports feel fresh to people, this will too."

THE SPOTS: Adweek asked the current creative directors on ESPN at Wieden + Kennedy New York to name their 10 favorite "This is SportsCenter" commercials through the years. Here are their picks:

—WIEDEN + KENNEDY'S 10 FAVORITE SPORTSCENTER ADS—

The Kid