U.S. officials keep instituting measures to bolster security on the nation's borders, particularly its land borders, but they are finding it tricky to do so without putting a damper on commerce levels.

Some of the biggest advances in border security so far have come from the Free and Secure Trade lanes program, the Container Security Initiative and the Smart Border Action Plan, among others.

While the names may sound like an attempt to mask serious programs with catchy phrases, Homeland Security Department officials say they aren't joking around.

"The threat of a terrorist attack using a cargo container is not just an academic one," U.S. Customs and Border Protection Commissioner Robert Bonner (search) said recently.

Earlier this month, outgoing Homeland Security Secretary Tom Ridge joined Mexican Interior Secretary Santiago Creel at the port of entry at Calexico, Calif., to formally open lanes dedicated to cargo trucks enrolled in a U.S. Customs and Border Protection initiative. The goal of the roads is to battle terrorism while still facilitating trade at the southern border.

The Free and Secure Trade (search) program is a quicker clearance program for known "low-risk" cargo shipments traveling between Canada and the United States and Mexico and the United States.

"Mexico is one of our largest trading partners and it is critical that we prevent terrorists from infiltrating the commercial chain to launch an attack," Ridge said. "This lane will enhance the security and safety of the commercial flow of goods along the southern border, while enhancing the economic prosperity of both countries."

By the end of 2005, 50 ports are expected to participate in the Container Security Initiative (search), which tracks U.S.-bound goods from their points of origin and calls for the inspection of cargo if certain criteria are met. Currently, 24 ports participate in CSI, with the port in Marseilles, France, most recently coming online.

Officials offer several examples of why CSI, established in January 2002, is not academic. Shortly after the Sept. 11, 2001, terror attacks, Italian authorities found a suspected Al Qaeda (search) operative inside a shipping container bound for Halifax, Nova Scotia. The container originated in Port Said, Egypt, and inside the container were airport maps and a phony airplane mechanic’s certificate, Bonner said. Much more recently, two homicide bombers entered the port of Ashdod, Israel, by hiding inside a cargo container. They ended up killing dozens of people.

"When you think about it, the container is the potential Trojan horse of the 21st century," Bonner said, adding that "the sum of all fears is a 'nuke-in-a-box.'"

Through CSI, an automated targeting system requires all cargo shipped to the United States from foreign seaports to be input into an electronic information system. Each container is then evaluated for terrorist risk before it is loaded and shipped. "High risk" containers are inspected before they're loaded.

Private sector partners have helped out with the program in an effort to boost security without slowing down the supply chain. They have created a private-public cooperation called the Customs-Trade Partnership Against Terrorism (search). Goods from companies that participate get faster processing through U.S. ports upon arrival. More than 8,000 companies currently participate in the program.

"We can't keep up with all the requests," Adam Wysocki, operations branch chief for CSI in the Office of International Affairs at the U.S. Customs and Border Protection agency, told FOXNews.com of the efforts to keep shipments moving. "I think the program has been successful on a number of fronts."

But some industry experts say that initiatives such as CSI aren't up to par — particularly the technology used to screen potentially dangerous cargo and material headed for the United States.

"Most inspection technology out there today are old, gamma-based machines," said Peter Kant, former vice president of Jefferson Consulting (search), which represents various container and transportation security firms as well as other security companies.

"We took the technology we were already buying for drug interdiction and we're saying, 'OK, now you're homeland security.' They don't work for homeland security. You can't see bombs, you can't see sarin gas, you can't see any of this stuff, but we're 'inspecting cargo.' That's not an inspection."

Wysocki acknowledged that cargo coming through ports from known shippers and trusted companies likely doesn't get inspected. But, he said, many CSI shipments that are routinely inspected are "high-risk shipments," meaning they come from countries or shippers that are "high risk" or that could include dual-use commodities.

"Like anything, there's the Rolls Royce and there's the Volkswagen," Wysocki said of the inspection technology. "Objectively, our intent is as you look at an image, regardless of the system," if the substance inside can't be identified, it would be inspected by hand, he added.

But Kant argued the background check and inspection "have to go hand in hand.

"It's a huge gaping hole and it has yet to be corrected … what's been done now is a small step forward but what needs to happen is a giant leap forward," Kant said.

Smart Border Plans in Play

Attaché offices have been established in both Canada and Mexico to increase the U.S. presence at ports of its two biggest trading partners. The offices were opened last fall and are responsible for implementing Customs and Border Protection (search) programs at the borders. Customs officials are working on improving visa policy coordination, compatible immigration databases and sharing advanced flight passenger information.

"We view the establishment of those offices as critical to our border operation security … coordinating efforts with Canada and Mexico," Roger Urbanksi, executive director for foreign operations at CBP, told FOXNews.com.

In his visit to Canada shortly before the new year, President Bush emphasized the U.S. commitment to securing its northern border while maintaining the speed of trade. He focused less on shipped cargo than on human threats.

"We've got an obligation to defend our respective countries and I am impressed by the prime minister's commitment to work jointly to share intelligence and to share information so that we can prevent those who would do harm to either the United States or Canada from being able to do so," Bush said during a meeting with Canadian Prime Minister Paul Martin (search) in Ottawa.

"[That] presents a challenge. And that is, how do we make sure those who are coming from the United States into Canada are known to both sides, and/or vice-versa. And, at the same time, how do we make sure that we expedite trade and commerce? I think we're making very good progress toward that end."

Bush cited the Smart Border Action Plan, an initiative the United States and Canada have developed to secure travel documents, increase intelligence sharing, improve the collection and dissemination of passenger and customs data and adopt rules for better processing.

In addition to that effort, the two countries are expanding transit for so-called "trusted travelers" crossing by land and air. The NEXUS Highway program operates at 11 border crossings on the road. NEXUS Air, piloted in November at Vancouver International Airport in British Columbia, has also been installed in certain areas of the United States.

The programs use iris-recognition biometric technology to identify individuals and confirm their admissibility into the countries. The two countries are also working to develop a NEXUS Marine pilot program to be launched this spring near Detroit.

Stopping Arrivals Before They Depart

Another program likely to be expanded this year as part of the Immigration Action Plan (IAP) is part of an effort to stop people with false or wrong identification documents before they get to the United States. The intelligence reform bill recently signed into law includes plans to expand IAP.

The program was piloted at an airport in Warsaw, Poland, after Polish officials expressed concern that too many Poles were being sent back to their home country after they arrived in the United States and it was discovered they had overstayed prior visa requirements.

"It's a forward-looking, proactive effort by CBP to place officers at international hub airports primarily to counteract smuggling of persons, the travel of inadmissible persons … and, in general, to improve air passenger and air safety," Urbanski said.

"We think it's a success and it avoids the difficulty to travelers having flown all the way to the United States only to be flown back," he added.

Other programs underway include the Integrated Border Enforcement Teams, multi-agency law enforcement teams that target cross-border criminal and terrorist activity, and radio-frequency technology testing as part of the US-VISIT program. US-VISIT tracks when and where foreign visa-holders enter the United States and when they leave, among other things.

"Through the use of radio-frequency technology, we see the potential to not only improve the security of our country, but also to make the most important infrastructure enhancements to the U.S. land borders in more than fifty years," said Asa Hutchinson, outgoing undersecretary for border and transportation security.