When Canadian rap star Choclair and his manager Lee “Day” Fredericks went to marketers looking to leverage the hip-hop artist’s popularity, they didn’t have to introduce themselves. Choclair’s debut album, 1999’s Ice Cold, had already yielded two hit singles, videos and coast-to-coast radio airplay.

‍     “We didn’t have to do any selling,” Mr. Fredericks said. “The demand was already there, and the success of the record proved it.”

‍     Marketers could see how that demand offered a platform for getting their messages to a coveted demographic: skeptical, hard-to-impress 18-to 24-year-olds.

‍     Marketing executives may not understand hip-hop. But they understand sales, and Choclair’s numbers demonstrate that.

‍     “When their kids love Choclair, it becomes very apparent what’s hip and what’s not,” said Mr. Fredericks.

‍     “It’s unfortunate that it’s only been in the last two years in Canada, but that is the reality, and advertising agencies are only just starting to become comfortable.”

‍     Choclair featured Microsoft’s X-Box gaming unit in a video before it was available publicly. His image was enhanced because he had an anticipated gadget before anybody else; Microsoft got its game unit associated with an eagerly emulated style-setter.

‍     Hip-hop accounts for more than 20% of music sales in urban areas in the United States, according to the Soundscan music retail measuring service. It’s been a pillar of pop culture for more than 20 years. But advertisers are just starting to notice, and to look for ways to capitalize on its popularity.

‍     Reebok wanted to forge relationships with home-grown hip-hop stars when it launched its Mustang shoe. Choclair was launching a CD at the same time. “So we launched our shoe and his CD the same day,” said Micki Rivers, Reebok Canada’s marketing manager.

‍     A cardboard stand-up of Choclair was in every Athlete’s World store across the country. He rapped in a Reebok commercial, and Reebok helped stretch Virgin Music’s promotional budget to push his album.

‍     “All of a sudden Reebok’s got a Canadian face,” Ms. Rivers said.

‍     The campaign won Reebok Canada the corporation’s global marketing award for 2002. “It was a mutual thing,” Ms. Rivers said. “Good for him, good for us”

‍     Reebok is currently crafting a campaign that brings together Canadian artist Jully Black with its shoes as well as National Basketball Association and National Football League apparel, for which Reebok is the sole licensee — something that gets it a lot of cachet and credibility in the hip-hop community.

‍     Rap’s relationship with marketing has existed for years, but on an informal basis — rappers named products in their lyrics without the urging of the products’ manufacturers. It started in 1979, with the Sugarhill Gang’s “Rapper’s Delight” (“Hotel, motel, Holiday Inn”), and continued through Busta Rhymes and Sean “P Diddy” Combs’s “Pass The Courvoisier” this year, which helped accelerate the cognac’s sales to a double-digit pace.

‍     “But we didn’t pay Busta to write the song,” said Jack Shea, spokesman for Allied Domecq Spirits North America, which imports and distributes the drink. He said the song was an unexpected result of a marketing campaign Allied Domecq launched months earlier, which included sponsoring shows by emerging artists at parties in bars, aimed at getting what he calls “young urban tastemakers” to try Courvoisier in cocktails.

‍     “We’re flattered by the song,” said Mr. Shea. And grateful: The company now has an agreement with Busta Rhymes’s handler, Violator Management, to supply Courvoisier for his current tour’s post-concert parties.

‍     Similarly, Cadillac’s Escalade sport-utility vehicle is a favored ride among hip-hop artists, and a four-wheeled star in a lot of hip-hop videos. General Motors doesn’t have any product placement deals to ensure the Escalade is featured; individual dealers lend demo models for video shoots. One Escalade booster, the Atlanta-based rapper Ludacris, made Cadillac part of the rhyme scheme in his song “Southern Hospitality”: “Cadillac grills, Cadillac mills, check out the oil my Cadillac spills.” That refrain didn’t cost General Motors a dime.

‍     But Ludacris also illustrates the trouble marketers can stumble into trying to ally themselves with a culture they don’t know much about. Pepsi-Cola recently dropped commercials featuring Ludacris after Fox News Channel commentator Bill O’Reilly decried his explicit lyrics and consumers complained.

‍     Mr. Fredericks remains wary, too. He said Reebok’s Ms. Rivers is one of the few marketing people who “gets it,” along with a couple of people at ad agency MacLaren McCann. Other marketers have noticed the success and want some for themselves, he said “Choclair’s image fits; he’s not the crazy guy, and he doesn’t promote violence, but he’s not soft, either. When a sponsor puts their name behind the tour and the tour goes smoothly, and that’s coupled with a lot of press, that’s just great.”