The Boy Scouts of America has said it will allow openly gay youths to join the organisation while maintaining a ban on adult leaders, after a vote at its annual meeting in Texas.
The resolution will go into force on January 1 next year.
Sixty-one percent of the estimated 1,400 delegates to the meeting in Grapevine, Texas voted to end the ban that for decades has barred open homosexuality in the movement.
"The Boy Scouts of America will not sacrifice its mission, or the youth served by the movement, by allowing the organisation to be consumed by a single, divisive, and unresolved societal issue," the BSA said in a statement, adding that there were no plans to further review the issue.
"While people have different opinions about this policy, we can all agree that kids are better off when they are in Scouting."
The text said "no youth may be denied membership in the Boy Scouts of America on the basis of sexual orientation or preference alone."
The 103-year-old institution, famed for its outdoor training programmes and support of wholesome virtues, has close links to the country's conservative and religious heartland.
The group, which is separate from the Girl Scouts of the USA, counts 2.6 million boys in its membership.
The Supreme Court ruled in 2000 in favour of the Boy Scouts, saying that the prohibition against openly homosexual members was part of its right as a private organisation to free association.