Donna Ferrato started out photographing pleasure. She ended up confronting pain.

While following the story of sexual adventurers, she stood stunned in the bathroom doorway of a New Jersey mansion while a man screamed at his wife. As he pulled back his right arm, Ms. Ferrato raised her camera and took a picture. As he slapped his wife in the face, she closed her eyes — and took another frame.

She saw herself in the mirrors as she kept photographing. But when he hauled off to strike her again, Ms. Ferrato grabbed the man’s arm and told him to stop.

“I said: ‘What are you doing? You are really going to hurt her,’ ” she said. “He threw me down and said: ‘I’m not going to hurt her — she’s my wife. I know what my strength is but I have to teach her that she can’t lie to me.’ ”

Donna Ferrato

That moment changed Ms. Ferrato’s life, leading to a decade photographing domestic violence and culminating in the book “Living With the Enemy.” Equally important, it set her on a long career as an advocate for battered women, helping to change how abuse is viewed and how it is handled by doctors and law enforcement officers.

Now she is beginning a campaign to encourage women to leave abusive relationships. For the last 30 years, she said, the emphasis has been on educating society as to why men are abusive, rather than why women stay with them.

“We’ve always tried to avoid that question,” she said. “I want the woman, especially if she is a mother, to feel the responsibility. If she’s got children, she can’t stay with a man like this. Her children are in too much jeopardy.”

Ms. Ferrato had been intrigued by pleasure, photographing eroticism and sexual experimentation. She met the New Jersey couple, Garth and Lisa, while photographing at New York’s famed sex club, Plato’s Retreat, and she often stayed at their Jersey mansion photographing their “swinger” lifestyle.

“It was a complete accident,” she said. “I like to see people having a good time. As a young photographer I was kind of whimsical, not into heavy-duty documentary, going to war or solving the world’s problems. I really believed that it was important for women to be sexually liberated.”

But the photos that Ms. Ferrato took that day — and over the next decade — helped change how domestic violence was viewed in America. She spent the 1980s living with victims and their abusers, staying in battered-women’s shelters and accompanying police officers rushing to domestic conflicts.

The result was her seminal book, “Living With the Enemy,” which Aperture has reprinted four times over the last 20 years. It is the rarest of photographic projects: one that has significantly affected the problem it documents, helping to change laws and establish and finance domestic violence shelters throughout the country.

Donna Ferrato

Part of that reason is that Ms. Ferrato herself became an energetic advocate for the abused women. She has given hundreds of lectures on domestic violence to lawyers, judges, police chiefs, mayors, medical groups and students. In turn, she has been honored for her activism and art, winning journalism awards for her courage and humanism, and even having New York City declare Oct. 30, 2008, “Donna Ferrato Appreciation Day” in recognition of her work.

Her current campaign to help women leave abusive relationships was a logical next step, born of a sharp critique of the movement she helped build. She wants people to again focus on why women stay, and to provide services to those who want to escape the abuse.

“But we have to make society stronger to help women transition from shelters, give them jobs, support, education and create a society that will be on their side,” she said. “Then, we can unequivocally say, ‘Don’t go back.’ ”

While Ms. Ferrato thinks that the legal system has improved for battered women, she says it remains unfair and women should not put too much faith in family courts. But unlike some advocates, she believes in rehabilitation for batterers through education programs that last between three and five years.

“I have more compassion for men than I used to have,” Ms. Ferrato admitted. “I believe in talking things through and being very serious about what needs to change and working on that. I’ve learned how to listen to people a lot more carefully. I’m not a very patient person and I can get mad. I understand myself better and see where some of my anger comes from and how to control it.”

She has continued to document the people she encountered during her project’s early years. Lisa and Garth divorced more than 20 years ago, and he died last summer. Diamond — the young boy in Slide 3, who witnessed the arrest of his father for hitting his mother — has grown up to be a hairdresser.

Donna Ferrato

She has incorporated the theme of domestic abuse into her workshops, training other photographers to continue her work on domestic abuse. And while it seems jarring at first, she also continued to document extreme eroticism. Her images are explicit, and most are rarely published or exhibited, although some were included in her book “Love & Lust.”

It might appear impossible to reconcile the two seemingly discordant narratives of Ms. Ferrato’s photographic career. Yet they share a common foundation: both are unflinching, intimate explorations of the deeply personal. And both make the viewer uncomfortable.

“I want to start a revolution with my pictures,” she said. “I want to wake people up, make people feel things — either suffering or incredible pleasure, or whatever I am feeling or observing.”

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