They are engineers, financiers, attorneys and physicians. They have won Nobel prizes, flown in space and hold executive-level positions at some of the largest and most influential companies in the world.

South Asians have contributed more to America’s economic might than perhaps any other ethnic group, but for those individuals lacking U.S. citizenship or a green card, the question remains — who gets to stay?

In the post-Sept. 11 era, where security concerns have led to tighter immigration policies, the answer is simple — very few. And in most instances, luck is the determining factor over whether one stays or goes.

"Our current immigration system is out of whack," Rajiv Khanna, founder and principle attorney at the Law Offices of Rajiv S. Khanna P.C. in Arlington, Va., said. "It was set up on the assumption that the green card process would take between eight to 12 months, yet on average, Indians need about four to six years to complete it."

Khanna, a specialist in U.S. immigration laws, also runs Immigration.com, a popular Web site that provides detailed information about the U.S. Immigration and Nationality Act, including bills under consideration by Congress.

He said current U.S. immigration policies have created a backlog of cases so deep, many highly educated and skilled South Asians living and working in America have been forced to return to their homelands. He blamed the United States Citizenship and Immigration Service for the quagmire and warned the United States risks losing its competitive edge because other nations are poaching South Asian workers who have been denied work visas in the United States.

"There are too many applicants and too few green cards," he said. "It's incredible that we've put an inefficient agency like the USCIS in charge of this process. I guarantee that if this continues for another five years, the U.S. economy will suffer the consequences."

Increasing U.S. competitiveness by providing more visas for skilled workers has been a sticking point in the ongoing debate in Congress over comprehensive immigration reform. Lawmakers have filed several bills that would increase the annual allotment of H-1B visas from 65,000 to 115,000, plus the continuation of 20,000 visas issued to applicants who hold advanced degrees from U.S. universities.

The employer-sponsored H-1B program allows nonimmigrant workers to enter the country for up to six years to fill labor shortages in fields such as computer programming, engineering, medicine, education and journalism. Companies submit requests for the visas based on projected labor needs, but aren't always granted the full amount of visas requested.

High tech firms in America and abroad have long complained that too few visas are available. They argue the industry is falling short of qualified scientists and computer programmers, and are pushing Congress to increase the number of H-1B visas as part of the comprehensive immigration reforms under consideration.

The U.S. Citizenship and Immigration Service received approximately 150,000 applications for the 65,000 available H-1B visas on April 2 — the first and only day that the agency accepted applications.

Microsoft Inc. chairman Bill Gates described the situation as an "acute crisis" during testimony before the Senate Health Education Labor and Pension Committee on March 7 and warned the shortage of H-1B visas will hamper efforts within the U.S. education system to improve math and science curricula.

Google Inc. vice president of people operations Laszlo Block said in a June 6 speech to the House Judiciary Subcommittee on Immigration, Citizenship, Refugees, Border Security and International Law that foreign nationals have launched nearly one-quarter of U.S. venture-backed public companies over the last 15 years, accounting for more than $500 billion in market capitalization.

The list includes such heavyweights as Google Inc., Intel Corp. eBay Inc., Yahoo! Inc. and Sun Microsystems Inc.

Both Google and Microsoft are charter members of Compete America, an industry trade group of several hundred IT firms, universities and research organizations that has called on Congress to boost the number of H-1B visa and employment-based green cards available.

"For many U.S. employers, the H-1B is an interim step to permanent resident status. The shortage of [green cards] is just as severe as the H-1B shortage. The green card program is essential if we are to retain highly skilled professionals who are already here contributing to our economy," the organization said in a statement. "However, most green card applicants face delays in excess of five years, and these delays are getting worse, not better. Furthermore, massive, multiyear backlogs in the green card program are causing a massive recruiting and retention crisis for employers."

But American companies aren't the only ones begging Congress to raise annual green card and H-1B caps — India's technology industry, which maintains a significant presence in the United States, has repeatedly asked Washington to relax visa rules for foreign-born software and computer professionals.

The National Association of Software and Services Companies — an Indian business group that connects the country's software and business-process outsourcing industries, said in a May 30 letter to the U.S. Senate that "constraining the supply when demand is high gives rise to problems for both U.S. companies as well as Indian IT companies. NASSCOM feels that the cap should be large enough to allow market forces to operate freely."

The organization issued the letter in response to Senate Assistant Majority Leader Richard Durbin, an Illinois democrat, and Iowa Republican Sen. Charles Grassley, who in mid-May asked nine Indian companies operating in the United States to explain how they use their work permits. Durbin and Grassley said in a May 14 letter to the companies that they had received reports of fraud and abuse of the H-1B program.

"More and more it appears that companies are using the H-1B visas to displace qualified American workers," Grassley said.

The senators suggested that some visas were being used to train foreign workers in the United States to perform jobs that were later transferred to India and other countries. "The reality is that too many H-1B visas are being used to facilitate the outsourcing of American jobs to other countries," Durbin said.

The senators introduced on April 2 the "H-1B and L-1 Visa Fraud and Abuse Prevention Act of 2007" which is designed to overhaul the H-1B and L-1 visa programs to give priority to American workers and crack down on unscrupulous employers who hire undocumented workers for less-than-minimum wages.

The proposal is just one of three such bills that Congress has or is debating this spring; the other two include a measure from Sen. John Cornyn, Republican of Texas, which would raise the H-1B cap significantly, and a similar bill from Sens. Joe Lieberman, I-Conn., and Chuck Haegel, R-Neb., which includes weak protections resembling some of those found in the Durbin-Grassley measure.

Ron Hira, an assistant professor of public policy at Rochester Institute of Technology, said of the three, the Durbin-Grassley bill would do the most to fix many of the flaws and problems

"It encourages employers to make an active, good faith effort to look for Americans workers, and it says you should pay foreign workers a good wage, and there should be some oversight to make sure that happens," he said.

Hira criticized the arguments used by the Indian technology firms and Corporate America in support of a H-1B cap increase as "clouded" and a "bait-and switch."

"The tech firms want to bring in more highly skilled workers that they can pay lower wages, but they can't do that without a cap increase," he said. "To them, visa caps are essentially barriers to trade.

"What most of the U.S. tech industry has done is frame the H-1B program as a bridge to immigration, a step to permanent residence here for foreign workers," he added. "In reality, these companies use it for outsourcing. They've denied that repeatedly, but they know that's what they're doing. Some of them have even admitted it in the past."

President George W. Bush looked noticeably glum as he approached the podium at the Naval War College in Newport, R.I., the afternoon of June 28. It was uncharacteristic of Bush, who is known for remaining optimistic even in the toughest of times. Bush fiddled with his papers as he talked about the Senate's resounding defeat of a last-ditch attempt to reform the nation's immigration laws. Then did something he almost never does:  he admitted defeat.

"A lot of us worked hard to see if we couldn't find a common ground," he said after the bipartisan measure — which he backed — died on Capitol Hill. "It didn't work."

Congress has all but given up on passing a comprehensive immigration reform bill this year. Lawmakers have conceded that any reforms will not occur until after the Nov. 2008 presidential election.