The Al Hamed construction labor camp is a hardscrabble jumble of battered trailers where 7,800 laborers sleep, cook meals and kneel to pray in an outdoor pavilion of corrugated tin.

The camp lies on Dubai's desert outskirts, out of view of the wealthy foreigners in the shoreline skyscrapers and the tourists thronging to mall boutiques like Prada and Gucci.

The workers in this camp, however, know the city's luxurious attractions. They built them, on salaries that range from $135 to $400 a month.

Despite their low wages, and despite the tens of billions of dollars in oil revenue pouring into the United Arab Emirates, laborers sometimes have trouble coaxing their employers to pay up. Three to five months without pay is common. Some say they have not seen salaries in a year or longer.

In the past, the docile immigrant workforce had little redress. But this year, thousands of laborers have walked off construction sites, blocking roads, marching in protest to the Labor Ministry or simply refusing to work.

"Any worker who doesn't get paid should go on strike," said a 33-year-old Indian man visiting the Dubai Court's labor section who gave his name only as Zia, for fear of being fired and deported for speaking to a reporter. "You have to go on strike, because it is successful."

Zia was one of a dozen laborers filing grievances last month for as much as six months of back pay.

The protests have galvanized the federal Labor Ministry into cracking down on the offending companies, saying they are tarnishing the reputation of the country just as it negotiates a free trade agreement with the United States. Workers' rights are a critical factor in those talks.

By the Labor Ministry's count, unpaid workers have organized 18 strikes this year, involving more than 10,000 protesters. Most were in Dubai, the wealthiest of the country's seven emirates.

Labor Undersecretary Khalid Alkhazraji promised last month to name offending companies and their owners, an unprecedented step since royal family members who own companies could be painted in an unfavorable light. Three companies have been named publicly -- none of them with openly royal connections.

"If they don't care about our country's reputation, we don't care about their reputation," Alkhazraji said.

This week, the ministry announced a hotline for laborers to report unpaid wages.

Nearly a million migrants from India, Pakistan, Bangladesh, China and elsewhere have poured into this desert sheikdom to provide the low-wage muscle behind one of the world's great building booms. In five decades, Dubai has mushroomed from a primitive town of 20,000 to a gridlocked metropolis of 1.5 million.

Last year alone, the Emirates government in Abu Dhabi issued 500,000 visas for incoming workers -- a 20 percent increase in the country's workforce, Alkhazraji said.

Almost 98 percent of private-sector workers in the Emirates are foreigners, mostly men, who make up more than 80 percent of the country's 4 million inhabitants.

In most Gulf Arab states, the situation is similar. In Saudi Arabia, Kuwait, Qatar, Oman, Bahrain and the Emirates, lawyers here say, it has become customary for contractors to withhold migrants' passports and three or more months of wages to keep them from leaving. When a company has financial trouble, laborers feel the pain first, said Mohammed Roken, former chairman of the Emirates' Jurists Association.

Human Rights Watch and the State Department have criticized the Emirates and other Persian Gulf countries as centers of human trafficking and worker exploitation.

In Saudi Arabia, Human Rights Watch in 2004 said some Asian migrants worked in "slavery-like conditions."

The State Department last month upgraded its assessment of the Emirates and Qatar, but they remain on a watch list. Saudi Arabia and Kuwait still face sanctions that can be waived only by the president.

The Emirates has a big impetus to treat its workers better. The free trade pact it is negotiating with the United States stands to make this business-savvy country even more wealthy. Dubai is a duty-free trading hub, with some of the world's busiest air and sea ports. Washington has already signed free trade pacts with Bahrain and Oman that remain to be ratified by Congress.

Holding up the Emirates deal are U.S. demands that would give workers the right to form unions and bargain collectively, Alkhazraji acknowledged. He said trade unions could have huge economic consequences for the Emirates, perhaps slowing the building boom while radicalizing the workforce.

That already seems to be happening, and protest appears to pay.

In September, after about 1,000 workers from the Al Hamed camp blocked the city's main highway, the Labor Ministry ordered the company to pay three months' back wages within days. The company complied, but was also fined and banned from hiring more foreign workers and landing government contracts.

Although the Labor Ministry had intervened in disputes before, it had never come down so comprehensively on the side of workers, observers here say.

Back at the camp, the evening sun burnished the trailers as exhausted laborers in identical blue coveralls streamed off buses to fix dinner.

One worker said his lifestyle bore little correlation to the mighty achievements he was partly responsible for: turning the undulating desert into a Middle Eastern metropolis. "Maybe some are proud working here, building this Dubai," said the worker, a college-educated Indian man who refused to give his name for fear of losing his job. "But it's not fair. The country is making money, but what about the laborers?"

A laborer holds a cement bucket suspended from a crane at a work site in Dubai. In background, the towers of the Dubai Marina project.Asian workers prepare cement in Dubai, a city known for its luxurious attractions. Among projects underway there is the Burj Dubai, expected to be the world's tallest building.