LITTLE ROCK, Ark. - Wal-Mart Stores Inc., the nation's largest private employer, will now include gays and lesbians in its anti-discrimination policy, company officials said Wednesday.

Company spokesman Tom Williams said the policy will not affect benefits, which Wal-Mart does not offer to unmarried partners of any orientation, but he said sexual orientation will be added to the company's existing diversity-awareness training programs for employees.

Williams said the policy change had been considered for months and is now in effect. It is considered an internal communication and is not being publicly released.

"Our continued growth requires us to be one of the more desirable employers around, so we're clearly stating our acceptance for all of our associates," Williams said. "Otherwise, we could lose many talented employees, and we don't want that."

The change means nine of the 10 largest Fortune 500 companies now have rules prohibiting discrimination against gay employees, according to the Human Rights Campaign. The one exception is the Exxon Mobil Corp.

Wal-Mart's decision was hailed by gay advocacy groups as a sign of changing attitudes in corporate America in the treatment of gay employees.

"It's a tremendous step forward, a real symbol of how far we've come in recent years, and especially in the past few days," said Michael Adams, an attorney and spokesman for the Lambda Legal Defense and Education Fund, alluding to last week's U.S. Supreme Court (news - web sites) decision striking down anti-sodomy laws.

"Wal-Mart is a uniquely important company in this country," Adams said. "And they're known as a careful and cautious corporation, which will cause others to take a look at this issue."

Williams said the policy change "unfolded by itself" after discussions with employees and groups advocating the inclusion of gays and lesbians in anti-discrimination policies. He said the Supreme Court ruling was not a factor in the decision.

"We want all of our associates to feel they are treated with respect and valued, with no exceptions at all," Williams said.

The change was first reported by The New York Times in Wednesday editions after a letter was sent to the gay advocacy group Pride Foundation that said Wal-Mart would work to ensure that all of its personnel decisions, including recruitment, hiring, training and promotions, would be protected from discrimination based on sexual orientation.

Wal-Mart Stores, based in Bentonville, Ark., is the world's largest retailer, with over 1.1 million domestic employees.