“Gender freedom is the ultimate sexual revolution,” says D.C.-based attorney and self-described entrepreneur Martine Rothblatt, author of The Apartheid of Sex: A Manifesto on the Freedom of Gender (Crown). In Rothblatt’s opinion, genital differences do not determine an individual’s sexual identity. One’s sex is as irrelevant as one’s skin tone—and any social or legal division of society based on physical characteristics amounts to apartheid. Predictably, this rather simple notion has caused some controversy, and though Rothblatt feels that she’s had “a tremendously great response” to her work, she will admit that a certain call-in TV talk show in suburban Colorado, for instance, wasn’t too welcoming. While the hosts were perfectly nice, it seems the conservative viewing public had a problem with Rothblatt’s vision of “a world in which each person establishes their own sexual identity without reference to their genitals.” Significantly, Rothblatt practices what she preaches. A “transgender” person, she previously chsoe a masculine role, but today lives in a “unisexual lesbian marriage” and raises her four biological children. And, for the future, she sees potential in a “unisexual model” of sexual orientation. Computer technology, meeting on-line, virtual reality, and cybersex, she says, make subscribing to one gender or another much easier. Rothblatt discusses her book in a slide- illustrated lecture at 6 p.m. Tuesday, Feb. 21, at Lambda Rising.