If you pass Norrie on the sidewalk, you won't be able to tell if she is a man or a woman.
The 49-year-old walks through her gritty Sydney, Australia neighborhood barefoot and wearing a dress. She is flat-chested, has an Adam's Apple, medium-sized feet and sports a haircut that could be male or female -- short in the back and on the sides, with a mop of long hair on top. She wears little or no make-up.
Norrie goes by only one name and is a self-described 'spansexual.' She was the first person in the world ever to be issued identity papers that state: "Sex Not Specified."
"I see myself as male and female," she said. Norrie is happy to be referred to as "he" or "she" in conversation. But says she doesn't want her identity documents to be telling lies.
"In terms of M or F," Norrie said. "I'm not specifically M or F. You can't specify me as being male or you can't specify me as being female without committing a 'fudge' at the very least."
Two doctors examined Norrie and couldn't determine that she was one sex or the other, physically or psychologically. So the State of New South Wales issued her a document that states: "Sex Not Specified."
"There are men, women -- most of us fall into one of those categories," said Professor Walter Bockting from the University of Minnesota Medical School, who has been researching gender identity development. "But then there is a minority who falls in between."
Norrie was born, anatomically, as a normal boy in a small Scottish town. Her family immigrated to Australia when she was seven, where she grew from an awkward adolescent into a glamorous gay man.
"At that stage, I was very androgynous," Norrie said. "That was the 1980s when Boy George was allowed to do it, but don't you do it in real life!"
Norrie said that during the day, she was discriminated against at her job in a government office for her appearance and sexual orientation. At night, Norrie socialized with transvestites and transsexuals where she felt accepted.
Eventually, she started dressing in drag and came to believe she was a woman trapped in a man's body.
'Why Can't I Just be a Human Being?'
"I knew that I couldn't do the role of man," she explained. "The role of woman seemed to be one I was getting approval for and felt natural for me."
At the age of 27, Norrie had sex change surgery to remove her penis and testicles and to create a vagina. She said the first couple of years after her surgery were liberating.
"I was absolutely ecstatic about it," she said. "Until I got involved with straight guys who, when they found out I was a 'trannie,' told me I wasn't a female. They felt they'd been lied to. I was threatened with violence."
Norrie explained that she then began to question gender itself, the simple male/female dichotomy. It's a question that Professor Bockting has been researching for the past 25 years.
"Historically, there have always been transgender people," he said. "There were cultures where there were more than two genders."
Bockting explained that some Native American tribes had a third gender: The "berdache" or men who lived as women. To this day, a third gender is socially accepted in Thailand: the "Kathoey," or lady boys. Across South Asia, the Hijra, most of whom are born outwardly male, have surgery and choose to live like women, remain an important, mystical part of Hindu culture.
"I think in the last century in our Western thinking, we very much went to thinking about people as either men or women," Bockting said.
Two years after her surgery, Norrie said she felt like neither a man nor a woman and stopped the hormone regimen that had softened her skin, produced breast tissue and broadened her hips to make her look feminine.
"I had to challenge the idea that I had to take my identity from a bottle," she said. "I had to open a cupboard every day and take these pills because I'm a woman and they make me a woman. What? Why can't I just be me? Why can't I just be a human being?"
Bockting said that it's not uncommon for people who have gone through a sex change to begin thinking about and questioning their gender identity again.
Norrie Says She's Fighting to Keep Her Status
"There are certainly transgender people who are born male, who live as a woman, who feel that way 100 percent, but that's not true for everyone," he said. "Maybe they have a little bit of both."
Norrie is one such "in between" person who has a little bit of both. She said she even chooses to walk around barefoot because shoes are too obviously a male/female marker.
"A long journey getting there," she said. "But once I realized I was comfortable being androgynous and realized I had a right to assert that ... things are pretty good."
According to the U.S. Dept. of Health and Human Services, about one out of 2,000 babies are born with ambiguous genitals, where it's not obvious whether the child is a boy or a girl. They are anatomically intersex.
But this is not the case with Norrie, who was physically born a male but didn't feel, mentally, totally male. Surgically, she became a female but didn't feel, mentally, totally female. It seems that it's her brain that is intersex and new research shows a sex change isn't solely a physical alteration.
"Research right now does focus on the sexual differentiation of the brain," Bockting said. "We believe that the basis of gender identity is mostly in the brain."
Norrie said she guesses she's about "60/40 female" but is most comfortable presenting herself androgynously in her appearance as she "feels inside."
"For the last 20 years, I've been living outside the gender binary," she said. "Confronting all these forms that say are you male or female and saying 'no'."
Norrie's state-generated "Sex Not Specified" papers generated lots of publicity. Since then, the New South Wales government has revoked them, claiming the documents aren't legal and were issued in error.
Norrie is currently fighting to get her status back, not just for herself, she said, but also for anyone who doesn't feel like they are either "M" or "F."
"I want my passport not to say I'm male or female," she said. "Otherwise, someone's going to look at it, see me in a dress, and pick up my Adam's Apple, and think, I don't know, I'm al Qaeda in drag? I don't want my passport telling lies about me. That's important."