I saw this documentary 25 years ago, and, at the time, I was quite moved.
A sexual surrogate, sometimes called a surrogate partner, is a member of a sex therapy team consisting of client(s), supervising therapist, and surrogate. Some couples attend sexual surrogacy sessions together, while some people (either single or in a couple) attend them alone. The surrogate engages in education and often intimate physical contact and/or sexual activity with clients to achieve a therapeutic goal. Masters and Johnson introduced the practice in their textbook on Human Sexual Inadequacy, published in 1970.
In 1985, Maureen Sullivan was a Sex Surrogate. She allowed filmmaker Kirby Dick to record every aspect of the thearpy of two patients, who were given therapy free of charge in exchange for their consent. From The Wikipedia article about the film.
Private Practices focuses on sex surrogate Maureen Sullivan and two of her clients. Kipper, a 25-year-old college student, has had little sexual experience with women and seeks help overcoming his shyness. John, a 45-year-old divorcee, believes that his sexual inadequacies are preventing him from finding a new partner. Sullivan works with these men in an attempt to improve their body image, relationship skills, and sexual satisfaction. The film also shows how these patients interact with their friends, family members, and therapists. Many scenes focus on Sullivan, who discusses her history as a surrogate and describes her own relationship difficulties. In one scene, she and her brother confront their father about his abusive behavior and unwillingness to accept Maureen's career choice.
There's a lot in here about Maureen's own relationship issues, and she comes across as almost as wounded and vulnerable as her painfully awkward clients. For Maureen, this seems to have been a trust issue, as if she couldn't ask her clients to make their intimate relationship issues open to public scrutiny without making herself equally vulnerable.
This is the only version of this film that I could find online find without a pay wall or a membership wall, and it's been cut extensively, about 15 minutes shorter than the other versions, but the nudity and scenes of intimate sexuality that I remember from the late 80s seem to be largely intact. However it's the emotional intensity of the participants that make this film worth watching, and worth remembering.