U.S. Defense Secretary Ash Carter speaks during a press conference on May 11, 2016. (Photo by Justin Sullivan/Getty Images)

Defense Department Secretary Ashton Carter announced today that the military is ending its ban on transgender people serving openly in the military.

“We don’t want barriers unrelated to a person’s qualification to serve preventing us from recruiting or retaining the solider, sailor, airman or marine who can best accomplish the mission,” Carter said this afternoon.

Carter cited estimates from a RAND Corporation study that there are about 2,500 transgender people out of 1.3 million active duty service members, and 1,500 out of 825,000 in the reserves (the upper end of estimates are 7,000 and 4,000 respectively). “We’re talking about talented and trained Americans who are serving our country with honor and distinction,” Carter said.

Implementation begins today in stages. Within 90 days, the department will issue guidebooks for commanders, on how to lead transgender service members, and doctors, for providing transition-related care. At that point, currently serving transgender service members will be able to change their gender in the military’s personnel management systems. The full policy must be implemented by next year.

“This has been an educational process for a lot of people in the department, including me,” Carter said. “We had to take into account the unique nature of military readiness.” But he cited recommendations from the RAND study that there are minimal financial costs and no significant impact on readiness.

The military repealed the “Don’t Ask, Don’t Tell” for gay, lesbian, and bisexual service members in 2011, and Carter said the experience ending that policy has provided something of a template for successful implementation.

You can see the full announcement here.