LOS ANGELES - AVN Hall of Fame performer Nina Hartley turns 50 today, marking a milestone as she celebrates 25 years in the adult industry.

"From my very first time in adult, I knew that I was a lifer," Nina told AVN. "Sex is my thing, and sexual entertainment, sex education, and sex discussion is my métier. It’s what I do."

The Berkeley-bred blonde has been doing That Thing since late 1984, when she performed in five hardcore loops in a single debauched day at San Francisco's Lusty Lady Theatre.

"The guy who was shooting the loops was an old hippie who had done light shows at Haight-Ashbury," she said. "He was so good at shooting them that he would edit them in-camera; he'd have a finished, 20-minute loop with very little editing required. That was a rare film experience for me."

Ms. Hartley's first porn video proper was the ill-fated Atom Home Video epic Educating Nina. Written, produced and directed by Juliet "Aunt Peg" Anderson, the movie was an education for Nina in the timeless art of the porno scam.

"Juliet was my mentor for my first couple of years in the business. She had gotten all her friends to invest in this movie. She lost all the money, her investors lost it all — and she never recovered from that. She was one of us, and the company treated her like a rube. It was so wrong.

"It's less of an old boy's club now; back then, I don't think a woman had a chance. There was no recourse, no place to go, no court that would have dealt with it. It was a hard-learned lesson for me, and, I think, one of the reasons I never worked harder on building my own business. I realized that I'm not hard-headed, and I don't have the stomach for dealing with money-men."

Still, self-confessed "polymorphous perverse" Nina persevered with rare enthusiasm at a time when the jizz-biz was a Wild West shootout of drug-soaked sleaze and sketchy, big-money distro deals. She went on to become one of the icons of '80s porn in such titles as Mark Carriere's Debbie Duz Dishes.

"After Deep Throat and The Devil in Miss Jones, that was one of the first 10,000-unit sellers at the brick-and-mortar stores," she recalled. "It's a very fun, light and fluffy little porn movie, and I would love to see it reissued for a new generation of fans."

Back in the day, Ms. Hartley's outstanding ass was hailed as the best in the biz. A quarter-century later, Nina and her glutes still cause lava to erupt from the loins of the lonely.

"I had butt before J. Lo had butt, and I thank my mother for it every day," she laughed. "I used to think my butt was an annoyance that made clothes difficult to fit — so when I got into doing porn, I was delighted to find out that I was blessed with two very popular fetish objects: big, baby-blue eyes and that round butt with a high, small waist. I knew that it was a trademark, and it didn’t bother me at all. I like anal sex; I didn't do anal sex in the beginning, because I didn't do it in my personal life. But I always liked spanking and everything else people want to do to my ass."

Nina named Sunny Lane as an current heir to her 1980s Primo Posterior title.

"Of all the younger women, she is the one I have the most affinity to — she has a good attitude, she's smart, she's bubbly, and I think she's playing an extremely smart game," she said. "Of course, there's lots of great butts in the industry now. Ass is the new tits!"

Today, Nina is happier than ever — still sexy, still freaky, and still smart as the whip wielded by her loving husband, BDSM pro Ernest Greene. At 50, she gets to have her kink and eat it, too.

"I want to thank all of my fans for coming along for the ride," she said. "I want to thank AVN for supporting me, and I look forward to continuing my exploration of all things sexual. And I encourage viewers and performers to be mindful to take care of themselves. Sex is a wonderful thing — use it, don’t abuse it."

Nina ended with some advice to fellow porn actors:

"The most important thing for everyone is not to worry about what we do on camera, but to pay attention to what you do at home with your partner. Be generous, be kind, have fun."

Check out an exclusive Nina Hartley photo gallery here at AVN.com.