New Mexico is again the only U.S. state that sent its chief executive to an annual conference of governors from the Mexican and U.S. states along the border, fueling questions about whether the 30-year-old tradition has lost its way.

Arizona Gov. Jan Brewer canceled last year's gathering in Phoenix after Mexico's border governors boycotted the event because she had just signed a tough law against illegal immigration. The New Mexico governor at the time, Bill Richardson, convened a meeting in Santa Fe, but he was the only one of four U.S. border governors to show up.

Richardson was also the only U.S. governor at the 2009 conference in Monterrey, Mexico.

"The governors are in a position to set the agenda for border issues, but they haven't quite figured out how to do it," said Andrew Selee, director of the Woodrow Wilson Center's Mexico Institute in Washington. "This could be the one conference a year that everyone who cares about the border has to be at. It hasn't become that."

Current New Mexico Gov. Susana Martinez is the only U.S. governor at the 29th meeting, which began late Wednesday and ends Thursday in the Mexican port city of Ensenada, about 50 miles (80 kilometers) south of San Diego. Three of Mexico's six border governors attended the opening ceremony at a vineyard in the rustic Valle de Guadalupe region.

Brewer backed out Tuesday, depriving the gathering of some potential excitement after last year's fiasco. Her spokesman, Matthew Benson, said she needed to catch up on state business after a 10-day trip to China that ended Saturday.

The most important item on Brewer's schedule was a briefing Wednesday on reforming the state Child Protective Services agency, Benson said. He insisted that last year's meeting and the Mexican government's opposition to Arizona's immigration law played no role in her decision to stay home.

"There are a number of other new governors on both sides of the border. She was looking forward to meeting some of those governors and having a chance to sit down with them," Benson said.

California Gov. Jerry Brown considered going but is busy in Sacramento reviewing hundreds of bills for his signature, said his spokesman, Gil Duran.

Texas Gov. Rick Perry is raising money ahead of Friday's filing deadline for presidential campaign finance reports. He had fundraisers in Tennessee on Wednesday and in Tennessee, North Carolina and West Virginia on Thursday.

"Conversations about border issues between Texas and other states and the federal government are ongoing whether or not someone is attending border governors' conferences," said Perry spokeswoman Lucy Nashed.

It's a far cry from 2008, when California Gov. Arnold Schwarzenegger drew all nine other border governors to Hollywood. Many posed for a group photo dressed as characters from the "Terminator" movie.

The meetings have been forums for a host of shared opportunities and challenges from trade and cross-border violence to water rights and infrastructure needs since 1980, when the governors met in Ciudad Juarez, Mexico. Up to 1,200 people came in the early 1990s, leading to limits on attendance aimed at making the gatherings more intimate.

Part of the governors' challenge is that many decisions are made by federal governments, a dilemma also facing border city mayors who meet periodically to discuss issues like immigration and congested border crossings. Only one U.S. mayor _ Jerry Sanders of San Diego _ attended a meeting last year, and his city was the host. He left after welcoming remarks.

Mexican President Felipe Calderon sent two senior Cabinet secretaries to the opening ceremony, which ended in a fireworks display. Governors from California, Arizona and three Mexican states sent substitutes. Only Texas had no one represented on the dais.

Martinez, the first Latina governor in the United States, told the wine-sipping crowd she was confident the meeting would be fruitful.

The venue alternates each year between the United States and Mexico. Martinez hosts next year's conference in Albuquerque.