College students looking for fun over spring break are going to have some heavy company in this Mexican resort. President Bush and the leaders of Mexico and Canada are coming, too, bringing portfolios of problems, gun-toting security agents and traffic-clogging motorcades.

While thousands of U.S. students lounge on the beach, Bush, Mexican President Vicente Fox and Canadian Prime Minister Stephen Harper will grapple with issues like trade, terrorism and border and immigration problems.

The student crowds are smaller this year with the beachfront still rebounding from last year's Hurricane Wilma, and Mexican officials are no doubt hoping the international attention from the summit will help boost tourism again.

"Cancun will be the eyes of the world," said cab driver Luciano Salgado Campos as he drove past downed trees lining the road from the airport to the beachfront resorts. "President Bush will be able to see how much progress has been made already."

Fox's government has spent millions to rebuild the beaches and dredge sand from the ocean floor to replace what was swept away in October, when Wilma brought winds reaching 150 mph. Many hotels still are closed.

The three leaders will gather at the Fiesta Americana Condesa on Thursday and Friday. By Tuesday, police had already set up roadblocks around the perimeter and security forces patrolled from the air and water.

Bush plans to spend less than 48 hours in Cancun, squeezing in bilateral and group meetings and a visit to the Mayan ruins at Chichen Itza — a rare cultural detour for the president who normally keeps a tight diplomatic schedule on foreign visits.

With a debate over border security raging at home, Bush is using the summit to try to strengthen ties with leaders of America's northern and southern neighbors who have their own concerns about the flow of people and goods with the United States.

The summit comes a year after the three countries signed a pact at Baylor University near Bush's Texas ranch that was designed to make trade more efficient and borders more secure. The agreement, called the Security and Prosperity Partnership of North America, aims to combat terrorism and drug trafficking while making U.S., Mexican and Canadian products more competitive with imports from China and other nations.

Yet there are concerns, particularly on the Canadian side, about a new U.S. requirement going into effect next year that says anyone coming into the United States must show passports or other secure ID instead of a simple driver's license or birth certificate. Critics say it could slow commerce with the United States' largest trading partner. Meanwhile, Mexico is closely watching how the U.S. will change its laws concerning as many as 12 million illegal immigrants.

In Washington, the Senate began to debate the emotional issue this week, while hundreds of thousands of protesters took to the streets nationwide in protest. Some Republicans are demanding tougher border standards, including the installation of fencing and criminal penalties for those who sneak across, citing national security concerns in the post-Sept. 11 world.

Bush says border security is important, but he also insists that immigrants who are willing to work for low wages perform a vital contribution to the U.S. economy. He is pushing Congress for a visitor program that would let foreigners — many of whom have sneaked in over the Mexican border — work temporarily in the United States.

But Bush said the way to control U.S.-Mexico immigration in the long term is for Mexico to improve its economy.

"Moms and dads in Mexico are anxious to put food on the table for their children," Bush told reporters from Mexico and Canada earlier this week. "And, therefore, many of them are willing to come great distances and lengths to be able to provide for their families. And I think most people would rather be providing for their families close to their homes."

The three leaders plan joint meetings, and Bush also will talk privately with each leader on bilateral issues. The border passport requirement and a long-running dispute over tariffs on Canadian lumber are expected to be part of his first meeting with Harper, a conservative who has less than two months on the job leading traditionally liberal Canada.

Both Canada and Mexico objected to Bush's pursuit of war in Iraq, and the dispute strained relations in Bush's first term. But the president insisted this week that the relationship has remained strong because of their strong economic, cultural and historic ties.

"Face it, part of the problem that we had was because of my decision to go into Iraq," Bush said. And the government of both countries didn't agree. And I understand that. War is terrible, it's an awful thing. And yet we're still able to maintain good relations."