Jon Mandel’s hobby is fishing, while his day job, as chairman of MediaCom, consists of trying to land the best places for clients to advertise.

The latter “fish” aren’t exactly jumping these days.

“Advertisers must be more targeted and find communities or small groups where there is a commonality of interests,” he said during a recent interview in his New York office. “For instance, there is no more prime time TV. Everyone has a different prime time. Lifestyles have changed since the 1950s. Now it’s the individual’s priority and choice. The News at 6 may work for some audiences, but not all audiences.”

Working at one of the media buying and planning arms of global advertising conglomerate WPP Group PLC, Mr. Mandel and his 450 employees monitor and research press and broadcast outlets, then help advertisers plan campaigns. MediaCom’s clients include Procter & Gamble, Shell, GlaxoSmithKline, Royal Bank of Scotland, Nokia, Masterfoods, VW, and Universal.

The good news is that overall advertising budgets are growing, but the challenge for advertisers and their agencies is to pick the right spots and then properly tailor their messages.

“It’s ironic that we can highly craft media ‘buys’ to meet the targeted audience, and then the advertiser blows it by using the same exact commercial on the Weather Channel as they do for MTV, CNN, or the show ‘The Office.’ That’s absurd. This happens constantly. Then they think it’s TV’s fault,” he said.

“They should have the guts to make four or five commercials. If they are not willing to spend an extra half-million to make more commercials, they might as well take the $3 million they spend on media and just throw it away or give it to charity.”

Mr. Mandel said newspapers and some magazines also have challenges, such as declining circulation. In addition, there have been scandals concerning certain publications misleading advertisers about their numbers.

“If only print did as credible a job with their numbers as broadcasters did,” he said. “Circulation is one of the biggest issues, like the prime time question. Also, do people care about newspapers anymore? I can get even more cynical and say people think they’ve read a paper when they’ve only read the food section or sports section. I can get all depressed about the newspaper industry if I want to.”

Mr. Mandel says he believes that newsweeklies are doomed.

“How do they stay relevant weekly? They must do more in-depth analysis to survive,” he said.

Likewise, traditional radio faces challenges.

“I’m a huge fan of satellite radio,” he said. “I have it in all my cars, which is ridiculous since commercials pay my mortgage,” he said. “But local radio became unlistenable with all the clutter.”

Along with the music publishing business, radio has also suffered as a result of technologies such as iPods, iTunes, and file-sharing on the Internet.

“The problem wasn’t kids stealing music online. The problem was that the record companies made you buy a CD with eight songs on it that you didn’t care about and didn’t want to buy. It’s the same problem with local radio,” he said.

Media buyers and planners also get frustrated with advertising clients that don’t pay attention to their research or that pick the wrong outlet at inflated prices, he said.

“Take the ‘Today’ show,” Mr. Mandel said. “The reason why advertising on that show is overpriced is because every brand manager watches it. The question is, are you advertising to yourself or to your customers? We always tell advertisers to force yourselves as media professionals and put yourselves in the rest of the world’s shoes,” he said.

For instance, Mr. Mandel said he forces himself to watch hours of television every weekend, tuning into channels he would never have been interested in personally in order to research the available menu of offerings.

As a result of lifestyle changes and technology, the press and broadcast industry continues to fragment, but it will continue to grow and adapt.

“The media companies own print, television, and Web stuff. They don’t care which of their outlets wins attention. They’re agnostic. They’re utilities,” he said. “And the advertisers don’t care whether it’s a wood-burning stove, gas, or oil heat. They just want to be warm. And sell their messages.”

Mr. Mandel is a fan of “user-generated content.”

“I go to a fishing site that fishermen contribute to that will tell me how to catch striped bass in Montauk,” he said. “There’s a guy that runs this site, he sells a few ads to bait and tackle or charter boat guys and probably makes a living. It adds up.”