“Vietnam is not behind other countries on this issue,” said Ngo Duc Thinh, an expert on len dong, a Vietnamese shamanic dance tradition that has traditionally featured many gay performers. “L.G.B.T. people have the right to be happy — that’s a human right.”

Luong Minh Ngoc, the director of iSEE, a Vietnamese research outfit that advocates human rights, said that while legislative progress has been slow and the government often prioritizes other issues, she has found officials in the Justice Department and Health Ministry who are genuinely interested in improving laws that affect the gay community.

“We think the support is there,” she said, adding that gay rights issues are generally viewed in Vietnam within a moral context, rather than a political one.

That is notable because Vietnam is an authoritarian state, where hundreds of political dissidents have been jailed in recent years and the ruling Communist Party does not allow nonprofits or the news media to operate independently.

Michael DiGregorio, the Vietnam country representative for the Asia Foundation, said that gay rights issues were an “easy win” for the government, and a natural fit for international donors who saw them as an important civil rights issue in the country.

But Mr. DiGregorio said recent changes to legislation on gender, marriage and families had only been possible because they reflected a “live and let live” attitude toward gay rights that is widespread among many Vietnamese. He attributed the tolerance partly to local religious and spiritual practices that focus on ancestor worship — not a powerful God who decides what is right or wrong — and also to a Communist ideology that has never tackled what he called the “religious mantles of morality.”

Mr. DiGregorio said one example of that tolerance was the warm reception that the Vietnamese public gave to Ted Osius, the last United States ambassador to Vietnam, who frequently appeared in public with his spouse, Clayton Bond, and their two children. “I knew that this would not be regarded as something strange or unusual, and Ted was immediately accepted,” he said.