In September of 1989, NBC aired a message from Tom Brokaw. "The more you know about an impending disaster, the more likely you are to do something about it," the news anchor told his audience. "That's why we're embarking on a campaign of public service messages. The campaign is called, appropriately, 'The More You Know.'"

In the 25 years since, the campaign Brokaw introduced back then has expanded its purview to include definitions of "disaster" that are both broadened and narrowed from the original: unhealthful eating habits, low self-esteem, environmental crises, cyber-bullying. The More You Know has won Emmys. It has counted presidents and First Ladies, as well as TV stars, as participants. It has also won what might be the best demonstration of cultural ascendance: widespread parody. (Doo-doo-doo-DOOOO…)

The campaign has also varied, enormously—not just in its messaging, but in its tone. Many of the ads have been earnest-and-serious:

Some of them have been earnest-and-jokey:

Some have been self-parodying:

And some have straddled the line between fact and fiction:

The tone of the spots has changed greatly as The More You Know has made its way from experiment to formula. One thing that hasn't changed, though, is the idea at the heart of the campaign: the notion that a monolithic "You"—a You who knows things, and who could know even more things, and who is looking to broadcast television networks to assist in that enlightenment—can exist in the first place. As Brokaw explains it, "You want your audience to care about you and know that you care about them, and the issues that are important to them." The spots, he adds, are a way to "remind everyone of our obligation as citizens."

With that in mind, here's a little more to know about The More You Know. Because the more you … well, you know.

* * *

The public-service announcement has long existed in the form of newspaper ads. But the shape The More You Know takes—the short, jaunty video, with a single message—was born in the UK, in the 1930s. The spots, featuring (and often directed by) the actor Richard Massingham, included such broadly relevant, pragmatic topics as how to prevent the spread of illness, how to swim, and—yes—how to safely cross a road. They were not high-minded. They featured pretty much the opposite of stars and rainbows. They were essentially the "For Dummies" book series, in televised pseudo-slapstick. Massingham's films struck a chord, though, and when Britain entered the war, its government commissioned him for a new set of spots, to be focused on the war effort. The short films spread to the U.S.—fitting accompaniments to the printed posters of Rosie the Riveter and Uncle Sam.

Peace returned, but the ads remained. They were useful, the networks realized, not just as a way to fill the air during unsold advertising time between scheduled programming, but also as a way of meeting the newly formed FCC's standard of public interest. (The Communications Act of 1934—still the governing charter for broadcast television—required that the networks operate in the "public interest, convenience, and necessity.")

The ads tended to focus on cultural education (like this little treatment on office etiquette, from 1953):

They also focused on public safety (like this, from 1961):

As PSAs evolved, they often doubled down on their own implicit paternalism by targeting themselves to children. In the 1980s, cartoons like He-Man and the Masters of the Universe and G.I. Joe: A Real American Hero used PSAs as their show-closing epilogues. ("Knowing," Joe jauntily informed a generation, "is half the battle.") NBC itself had a dedicated series of kid- and teen-targeted PSAs in the '80s, too. "One to Grow On" aired during the network's kid-targeted Saturday morning lineup from 1983 to 1989. It focused on community, ethics, and personal safety. It included spots like this:

And like this:

And then, in the late 1980s, a group of education-focused nonprofits came to NBC with a request: They wanted the network's help in recruiting teachers. There was a shortage at the time, and the organizations wanted the network's help in raising not just people's respect for the profession, but also in having qualified applicants for open teaching positions across the country. NBC agreed. It recruited its star anchor, Tom Brokaw, to present The More You Know's first message, with the idea that the ads would be part of a larger PSA campaign featuring a variety of NBC talent. In 1990, NBC ran this ad, featuring Bill Cosby making the case to go into (or at least respect the profession of) teaching:

It has now become something of a rite of passage for TV personalities to do one of the spots. The recent crop of The More You Know message-givers includes Amy Poehler, Coolio, Joan Rivers, Jack McBrayer, Tiki Barber, Shakira, Usher, Steve Harvey, Anjelica Huston, Ken Jeong, Questlove, and Jimmy Fallon. (And also Al Roker, who explains that "it's exciting to be part of something that does good, that gets families talking about issues.")

Often, celebrities are personally connected to the causes they discuss in the spots. Seth Meyers's mother is a teacher; he did an ad about education. Ken Jeong, who was a physician before he was an actor, did a spot about health. As Beth Colleton, NBCUniversal's senior vice president for corporate social responsibility, told me: "The spots are authentic in the sense that the talent speak to things they really care about. And I think we've seen that over the years."  

NBC is also expanding the campaign to make it more accessible to audiences who are, increasingly, not parked in front of televisions. It now runs its video PSAs as banner ads on its websites—the better, Colleton notes, to reach audiences across different platforms. Last year, the network released an ebook, aimed at parents and teachers, discussing how to talk to kids about navigating the Internet. NBC has also been working with the channel Sprout to develop spots targeted to pre-schoolers and their families. And, earlier this year, the Today Show ran its own PSA campaign—one that dealt with body image issues. It made its program more interactive than most, asking people to tag images of themselves with the punny hashtag #loveyourselfie.

The campaign may evolve, but its star—earnestness—stays the same. Doo-doo-doo-DOOOO...