Juan Luis Guerra, a songwriter from the Dominican Republic, was the big winner at the eighth annual Latin Grammy Awards last night.

His “La Llave de Mi Corazón” (“The Key to My Heart”) was named album of the year as well as best merengue album; its title track, a cheerful song about a caller to a radio station’s romantic advice show, was named record of the year, song of the year and best tropical song. The album also won an award for audio engineering.

In an acceptance speech, Mr. Guerra spoke about the damage done to the Dominican Republic by Tropical Storm Noel, saying, “We are a strong and valiant nation.”

The Dominican Republic is only part of the far-flung coalition represented by the awards: From Spain to Argentina, Brazil to Puerto Rico, Portugal to Mexico. At the Latin Grammy Awards, which were telecast from the Mandalay Bay Events Center in Las Vegas by the Univision network, performers did a lot of geographical roll calls, name-checking as many countries as they could fit over a beat.

Ricky Martin, who started the show dancing through his “La Bomba,” won the best male pop vocal album award. In his speech, he called for more unity among Latin countries and urged people to learn English but also keep speaking Spanish.

The Puerto Rican reggaetón duo Calle 13 won the award for best urban music album with its ambitious, innovative “Residente o Visitante,” which has immigration issues, among other things, on its mind. The duos’s rapper, Residente, pointedly thanked the many Latinos working in the United States, from construction workers to doctors.

Calle 13 gave the most explosive performance of the telecast. Sharing the stage with Orishas — a Cuban hip-hop group now based in France — and with drummers from the Las Vegas production of Stomp and with Arauco Indians from Colombia, it delivered a frenetic, percussive performance of its song “Pal Norte,” about crossing borders, legally or not. “Pal Norte” was named best urban song.

The duo’s producer, Visitante, said in his speech that music and business should be kept separate. Two other reggaetón acts, Daddy Yankee and Ivy Queen, also had snazzy production numbers.

The Latin Grammys face a commercial fact: In the United States, by far the most consistently popular Latin music is rooted in Mexico. Mexican performers dominated the first part of the program: the singer Pepe Aguilar, who won the best ranchero album award, appeared with both a mariachi band and a banda (brass band) and sang about being “100 percent Mexican.” The winner of best pop album by a duo or group was the Mexican group La Quinta Estación, which belted a power-ballad medley. The best new artist was the pop-rock duo Jesse & Joy, from Mexico City.

While most of the show’s 48 awards were given before the telecast, Mexican music awards got plenty of air time. The award for best banda album went to Los Horóscopos de Durango, a rare banda with women as singers. The rock category had winners from Panama (Los Rabanes) and Argentina (Fito Paez, Gustavo Cerati).

Europe also had winners. Italy was represented when Laura Pausini won the best female pop vocal album award; she thanked Luciano Pavarotti, and sang a duet with Andrea Bocelli. Manu Chao, born in France but multilingual in his songs, won best alternative song for his “Me Llaman Calle” (“They Call Me the Street”).

The best alternative album was by Aterciopelados, from Colombia. In Brazilian music, the songwriter Caetano Veloso won two awards: best singer-songwriter album for his “Cê” and best Brazilian song for a song from that album. Other Latin Grammys for Brazilian music went to Lenine, Lobão, Zeca Pagodinho, Daniela Mercury, Cauby Peixoto and the collaboration of Leny Andrade and Cesar Mariano. In the tropical categories, which cover salsa, winners included Oscar d’Leon, from Venezuela, and El Gran Combo and Bobby Cruz, from Puerto Rico.

This year’s awards added a separate principality to the Latin coalition: Las Vegas. At times, the city received as much attention as the music, with jokes, video clips and omnipresent showgirls. Las Vegas has been making itself a magnet for awards shows, lately the MTV Video Music Awards. By now, the Vegas catchphrases about winners and luck are growing shopworn. And for Latin music — which is never short on sequins or hip-swiveling — Las Vegas glitz can be downright redundant.