Christine Potvin joined the military in 1988, the same year that she realized she was a lesbian – a year that other soldiers of a similar sexual orientation were being rooted out and expelled from the Canadian Armed Forces.

The military called it being "not advantageously employable due to homosexuality."

But Ms. Potvin desired the life she had seen on a recruiting poster. She wanted a job that would be physically demanding, taking advantage of her athletic nature, and that would give her a chance to see the world. So she walked into a recruiting office in Ottawa and enlisted, harbouring a secret that could have put a quick end to her military ambitions.

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Today, 29 years later, Warrant Officer Christine Potvin is the sergeant major of her medical company. And she is married to a woman.

There has been a profound culture change over the nearly three decades since WO Potvin joined the Forces. As she approaches her retirement next month, the military is openly welcoming gay and lesbian Canadians, trying to spread the word that discrimination and harassment are no longer tolerated, and that people of all sexual orientations can be promoted to the highest ranks.

WO Potvin, who is now 51, has a message for young homosexual people who are considering a career as a soldier, sailor or aviator.

"I would say don't be afraid to make that decision and take that step," she said. "With the newer generation coming in, and all of the policies and the support that the Forces have given to alternative lifestyles, I would say don't be afraid."

The year 1988 was a year of change for WO Potvin. "I was 21. The same year was the first year I had a relationship with a woman," she said. "It was still brand-new even to me."

She was aware from the moment that she signed her military papers that any overt suggestion of homosexuality could result in a humiliating interrogation by a Special Investigation Unit which had, by that time, forced the resignations of hundreds of others.

"Knowing that, I was quite careful and, the famous expression, 'in the closet,'" she said.

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The military is a family and her closest friends were aware that she was leading a double life. If others suspected, said WO Potvin, they did not approach her about it, perhaps as a way of protecting her.

Then came Michelle Douglas, a 2nd lieutenant who was discharged in 1989 under what was known as an "administrative release," the typical means of ejecting a homosexual from the military. Ms. Douglas launched a lawsuit that was settled in 1992 and prompted the government to strike down the law that prevented lesbians and gays from serving their country.

It still took some time for WO Potvin, who was trained as an operating-room technician, to be open about her sexuality.

"I would say maybe within the first five years I was quite careful and then, slowly but surely, I started coming out of the closet," she said. "In general, the attitudes towards gays and lesbians were changing. Of course, the attitudes towards women were changing also."

Through multiple deployments to Afghanistan, WO Potvin said she was never subjected to negative comments, either from Canadians or from the soldiers of other nationalities who worked alongside her. "What was important to them is that I was able to do my work as a soldier in a combat zone, in a war zone," she said.

Here at home, it took time for attitudes and policies to change.

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But Operation Honour, a strategy introduced in 2015 by Jonathan Vance, the Chief of Defence Staff, to end sexual assault and harassment within the Forces, has accelerated things considerably, said WO Potvin. "They are cleaning house and they are really working at restructuring the policies."

Lieutenant-General Charles Lamarre, the head of Military Personnel Command, which is the human-resources branch of the Forces, says there are no specific targets for the hiring of more gays and lesbians but the message is clear that they will be made to feel accepted and valued.

"We want to reflect Canadian society and, of course, that includes all the people who make up Canada and that includes sexual orientation as well," said Lt.-Gen. Lamarre. "What we can tell them is they are going to have a place where really it is a meritocracy, you are judged on your performance and how well you do your work and you get rewarded in the same way."

Today, there are gays and lesbians at the top echelons of the military, both at the officer and at the enlisted level. Rear Admiral Luc Cassivi, who is in charge of the Canadian Defence Academy, has a male partner.

It is a change that is welcomed by Michelle Douglas.

"It shows tremendous progress since the time when I was dismissed from the CAF because I am a lesbian," she said. "The military should be acknowledged for opening its arms widely to all those who wish to serve their country in the CAF. It is important to see diversity as a strength. Leadership on this will be key to ensure those from within the broad LGBTQ2 community are fully supported as members of the CAF and messages should be reinforced that there is zero tolerance for discrimination."

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As for WO Potvin, she is looking forward to a new chapter in her life when she is medically discharged in August. She plans to take a photography course and to spend more time with her wife in Ottawa.

Taking off the uniform for the final time will be emotional, she said, because her experience has, by and large, been so positive.

"You're not going to be able to educate everyone in terms of being human, and not being [looked at as] gay, straight, white, black … that's never going to happen 100-per-cent. We know that," said WO Potvin. "But if we each play our role, one at at time, we will reduce discrimination, we will reduce segregation."