As befits a pop music idol whose last record sold more than 4.5 million copies, Luis Miguel chose to do things on a grand scale when it came time to release his new album, "Aries," early this summer. Reporters and disk jockeys from all over the United States and as far away as Argentina were flown here to hear the 23-year-old singer discuss the making of the record (reported to have cost more than $1 million), watch him perform at a pair of sold-out concerts and see the premiere of a lavish, romantic music video, shot in three versions by three different directors.

Three months later, Luis Miguel, now in the midst of an American tour that took him to Madison Square Garden earlier this month and will peak in December with a five-day engagement at Caesar's Palace in Las Vegas, Nev., has proved to be worth every penny of that investment. Some 1.5 million copies of "Aries" have flown out of record stores throughout the Western Hemisphere, and the album's first single, "Ayer," can be heard on radios everywhere Spanish is spoken. Once again, Luis Miguel -- a Mexican born in Puerto Rico of Spanish-Italian parents whose full name is Luis Miguel Gallego -- has been confirmed as Latin heartthrob numero uno, the Julio Iglesias of his generation.

Just five years ago, success of such magnitude would have been inconceivable for a Spanish-language performer. But the Latin music business in the United States is being transformed by forces both cultural and commercial, and the lesson has not been lost on the multi-national record companies that have increasingly been making their presence felt in the market.

"This is now a big business," said Jose Behar, president of EMI Latin, a branch of the EMI conglomerate that did not even exist five years ago. "It's no longer a matter of going down to Pico Boulevard" -- a Los Angeles street lined with the mom-and-pop Latin music retail outlets that were once typical of the business -- "and visiting your three customers. This is an age in which it pays to have global vision."

But the success of Luis Miguel and bright new stars like Juan Luis Guerra, Gloria Trevi, Jon Secada, Selena, La Mafia and Jerry Rivera who appeal to a young audience looking for more driving rhythms than the crooners of the past could offer is, Mr. Behar and other industry executives are betting, merely a taste of things to come. Already a formidable market of more than 25 million people, Hispanic consumers in the United States are expected to overtake blacks in the next decade as the nation's largest minority group. Their numbers are being fed by continuing immigration from Latin America, but rising incomes and education levels have also created a young and vibrant bilingual Latino middle class that has billions of dollars to spend and a desire to maintain its cultural roots.

At the same time, growing economic integration with Mexico, culminating in the North American Free...