(CNN) -- Openly gay youths will be allowed to join scouting, delegates to the annual meeting of the Boy Scouts of America voted Thursday.
More than 60% of the group's 1,400-member national council voted in Grapevine, Texas, for the historic policy change, which will take effect January 1.
"No youth may be denied membership in the Boy Scouts of America on the basis of sexual orientation or preference alone," says the approved resolution.
The BSA will maintain its ban on gay adult leaders.
"The resolution also reinforces that Scouting is a youth program, and any sexual conduct, whether heterosexual or homosexual, by youth of Scouting age is contrary to the virtues of Scouting," the 103-year-old organization said in a statement.
The BSA said there are no plans for further review of the issue.
"The Boy Scouts of America will not sacrifice its mission, or the youth served by the movement, by allowing the organization to be consumed by a single, divisive, and unresolved societal issue," it said.
Reaction to Thursday's vote was swift.
The Human Rights Campaign said the BSA took a "historic step forward."
"Unfortunately, the new policy does not go far enough, leaving adult Eagle Scouts, scout leaders, and parents behind," the group said.
Jennifer Tyrrell, an Ohio mother who was ousted as a den leader in April 2012 because she's lesbian, called Thursday's vote "incredible."
"They've never been raised to discriminate against anyone regardless of sex or color or anything, so they can't understand why people care so much," she said of her children. "... Definitely, one day, I hope they look back and think that we're part of something amazing."
Tyrrell, in an interview with CNN affiliate KTVT, that the vote energized her for her next push -- to change Boy Scout policy so that gays and lesbian adults, like herself, can serve as leaders.
"When we used to exclude women from things, when we used to exclude black people from things, and that never has ever worked, but we continue to do it," she said. "I'm going to be around to make sure that that's not the case. We're definitely not going to go away."
Conservative groups and some religious organizations argued against making any change in the membership policy, saying it would dilute the Boy Scout message of morality and potentially destroy the organization.
John Stemberger, founder of OnMyHonor.net, which opposed the resolution, called the vote a "sad day for Scouting."
"It is with great sadness and deep disappointment that we recognize on this day that the most influential youth program in America has turned a tragic corner," Stemberger said. "The vote today to allow open and avowed homosexuality into Scouting will completely transform it into an unprincipled and risky proposition for parents."
The conservative Family Research Council tweeted: "Sadly, the @boyscouts' legacy of producing great leaders has become yet another casualty of moral compromise."
The vote followed months of intense debate among interest groups and within the ranks of Scouting itself.
In February, the Boy Scouts' national executive board postponed a vote on the issue and ordered a survey of its members.
That survey showed an organization divided by age and, in some cases, by region.
"While a majority of adults in the Scouting community support the BSA's current policy of excluding open and avowed homosexuals, young parents and teens tend to oppose the policy," the survey said.
A BSA spokesman at the time called the issue "among the most complex and challenging issues facing the BSA and society today."
A recent Washington Post-ABC News Poll showed that 63% of Americans said they would support allowing gay youths to join the Boy Scouts.
The vote comes more than a decade after the Supreme Court ruled that the organization has the right to keep out gays but also at a time of declining participation in the American institution.
Membership in Boy Scouts has declined by about a third since 1999. About 2.7 million people now participate nationwide.
The Church of Jesus Christ of Latter-day Saints, after the vote, said it will continue to work with the BSA.
"Sexual orientation has not previously been -- and is not now -- a disqualifying factor for boys who want to join Latter-day Saint Scout troops," it said in a statement.
The vote could have an impact in at least two Western states.
The heavily Mormon-populated states of Utah and Idaho reported that if a unilateral change in the policy were to be made, 97% of chartered organizations would probably leave the organization.
CNN's Greg Botelho, Katia Hetter and Ed Payne contributed to this report.