After six years of anguish and uncertainty, Tran Thi Hoai Van's dream of joining her husband and two sons in the United States has come true.

The fragile 41-year-old woman and her 20-year-old daughter were among the first group of Vietnamese recently allowed to leave Vietnam to join their families in this country. Their journey was part of the orderly departure program approved in 1979 by the United Nations and the Vietnamese government.

Van's story is familiar.

Her husband, Le Van Trung of Arlington, worked for the Americans in Vietnam throughout the United States' long involvement in Vietnam. In 1975, when it became apparent the North Vietnamese were on the point of overtaking Saigon (now Ho Chi Mihn City), Trung rushed his family to the U.S. embassy near the heart of the city. Trung and their two sons, now 13 and 16, clambered aboard a Marine helicopter which flew them in Navy ship waiting offshore.

Van and their daughter were not as lucky. As desperate crowds gathered outside the embassy compound, the two women found themselves unable to move -- and unable to reach the safety of the embassy grounds in time to join Trung and the boys.

After the North Vietnamese takeover, Van remained in Ho Chi Minh City. To survive, she worked as a vendor and, occassionally, she was able to receive some of the money her husband sent her during their separation.

But she never relented in her struggle to leave Vietnam, even though there were times that she and her daughter nearly lost hope.

Three years ago, Van's husband, who works for the Fairfax County Public Works Department, asked the U.S. Immigration and Naturalization Service to allow his wife and daughter to immigrate to this Service approved the request, the effort stopped there.

"(Trung) sent the documents to me," Van said, "but I put them in a drawer, since Vietnam at that time did not give any exit permit to the United States."

But in the spring of 1979, when Vietnam and the United Nations agreed to the orderly departure plan, Van once again began to hope. Under that plan, 1,357 Vietnamese left their country in December and January to join their families in the United States.

The plan, according to recently arrived Vietnamese, has caused a furor among their countrymen still in Vietnam. Crowds of people, disregarding police orders, have jammed the Emigration Office seeking permission to join their families in the United States. In turn, American refugee and immigration officials say Vietnamese here have bombarded immigration offices and voluntary agencies with applications for the program.

To obtain a exit visa under the program, Vietnamese applicants must have their names on a "joint working list" approved both by the government of Vietnam and the United Nations High Commissioner for Refugees. That list was put together after the United States and Vietnam exchanged lists of persons who might qualify for the program. The United States submitted a list of 17,000 names, while Vietnam submitted a list of 30,000.

For Van, first word that she might be able to reunite her family came when local authorities in Ho Chi Minh City called a meeting to explain the new policy. As always, Van was wary of the promises.

"Caution and distrust of communists taught me to adopt a wait-and-see attitude," she said. "I wanted to see someone move first."

Van did not take any action until a friend told her about a "desk for emigration" at her district police station. She went there for information and was given some forms to fill out.

"It took me two weeks to complete the dossier with biographical data, photos, birth certificates, act of marriage, family lists, residence certificate . . ." Her application was sent to the emigration office but she heard nothing for nearly a year.

Last August, she received a notice telling her to pick up her exit permit. "But three days later," she said, "I was 'invited' to the city police headquarters. They asked me about my personal histories and particularly about my husband.

"They kept questioning me. 'What did your husband do? Was he a CIA agent? Have you heard about CIA? Did he send letters to his friends in Vietnam?' I answered that he had worked for Americans but he did not tell me if it's CIA or not."

Her husband, Le Van Trung, said he had worked for the American consular office in Tay Ninh province, west of Saigon.

One day police asked her to rewrite her biographical data, and her feelings about the police and their treatment of her. Then, for a month, she had to report to police once a week to rewrite her biography and to describe her sentiments on family reunion and on leaving the country.

In early September, one year after her application date, Van and her daughter received their exit permits. "I was filled with joy, but I also felt uncertain about other things ahead," she said.

In November 1980, United Nations teams arrived in Vietnam to interview persons eligible for the orderly departure program. Van's interview came on Jan. 6 of this year, when a government official drove her and about 20 other people to a rural area about nine miles from Ho Chi Mihn City.

There, "Mr. Tom," Thomas Malia, an American working for the United Nations High Commissioner for Refugees, interviewed Van. Two days later, Van went for medical examinations.

"I was so happy and nervous," she said, "that I felt cold at hands and feet."

Still, her ordeal was not over. Although her exit permit had been approved, she had to get clearances on taxes, banks and property before she and her daughter were allowed to leave. For the property clearance, she had to sign a paper giving her house, valued at $10,000, to the Vietnamese government.

Finally, the day came when Van boarded a plane for a long-awaited reunion.

Two months ago, shortly after Van left Vietnam, the orderly departure program was suspended because, according to the State Department, officials had "exhausted" the names on the "joint working list." It is now known when the departures will resume, although State Department official Lloyd says officials hope it will be soon. "We are moderately optimistic," he said. "The program has worked well so far."

For Van, the long journey is over -- a journey with so many dips and turns that even as she was about to begin the flight to her family Van still feared her hopes would be shattered.

"Only when I was in the air," Van said recently, "did I feel confident that I surely was going to see my husband and sons."