Editor's Note: This is the first of two stories focusing on rape as a tool of war. The second story looks at the untold stories of rape in the Holocaust. Both stories contain graphic language; discretion is advised.

(CNN) -- It began as a headache. Then her throat started to feel tight. A dull pain welled in her chest and her joints ached.

But Victoria Sanford continued to do the interviews. Even in the middle of the night, the women in Guatemala always managed to find her, the "gringa" they heard had come to listen to them.

It was the early 1990s, years before the international community would formally recognize the Guatemalan government's role in the systematic rape of its Mayan women -- and decades before the current violence in Libya and elsewhere around the Middle East would once again remind the world of the brutal effectiveness of rape as a weapon of war.

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Sanford was then in her early 30s and pursuing an anthropology doctorate at Stanford University. A Spanish speaker who had worked with Central American refugees, she befriended the few Mayans who had moved to California.

"I was moved by their stories, but even more so because they were intent on someone hearing them," she said. "And no one was listening."

So Sanford joined the nonprofit Guatemalan Forensic Anthropology investigative team and went to Guatemala. The team's job was to exhume mass graves, but Sanford talked to the women, who told other women about her, and soon she was recording their stories.

Though she didn't realize it then, Sanford had joined a small fraternity of interviewers who spend months, sometimes years, in the globe's most perilous conflict zones listening to victims of war recount violence that would shock the sickest imagination. Their interviews often end up in a published study or news article, or in a report on a powerful bureaucrat's desk. They do it in part so that foreign policy can be more wisely shaped or money better directed.

But they also do it for a simpler reason: They believe that listening is acknowledgement -- and that acknowledgment is a kind of apology. Listening, they say, is the least the world owes.

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So they sit patiently and listen to the victims: The little girl who was raped in a Darfur refugee camp and made an amputee when her assailants tried to kill her by hacking off her arms and legs. The man in the Democratic Republic of Congo who told how a female general of a warring tribe turned him into a sex slave, and how the baby born of that assault is being kept from him as further manipulation. The Kosovo woman who can't help her spontaneous screams of rage while she tells how soldiers climbed on top of her, choked and beat her and did things too graphic to publish here.

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'They killed our babies'

In Guatemala, Sanford listened as the Mayan women -- disheveled, filthy, bruised and malnourished, their eyes dull and dead -- told how they hiked through the freezing mountains, fleeing guerrillas who were using their villages as hiding places from government soldiers who wanted the guerrillas dead:

The soldiers set fire to our villages. They shot our husbands and brothers, burned our houses. They stopped to wait for the sound of our babies crying. When they cried, the soldiers came toward the wailing.

They killed our babies. They raped us.

Sanford's tape recorder would click off every 60 minutes. She'd flip or replace the cassette, the women sometimes took hours to describe every detail. In order to spare their children death by a soldier, or to prevent a baby's cries from alerting soldiers, some mothers were forced to smother their own children, until they fell limp in their arms.

Sanford cried with the ones who seemed to want her to cry with them. She remained stoic if that's what they seemed to want.

Over the weeks, her stomach churned. She had trouble catching her breath. She felt odd, old, worn.

"What was I going to say, 'Please stop, you're traumatizing me?' "

"They are horrific, every single story, but they are there and you are there, and you are human. Part of me wanted to listen while another part of me felt stung."

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Inevitably, Sanford and other interviewers of war crimes victims absorb what psychiatrists call secondary trauma. A better word, perhaps, is found in the Mayan culture.

"Susto" is what the women she was interviewing called it when they noticed. She had "fright sickness."

One morning, the women's diagnosis showed itself in a horrifying way. Sanford woke up paralyzed.

"I couldn't move my neck or sit up. I couldn't move. I thought 'Oh God, how am I going to get in the car and go to these interviews?' It was so absurd."

"I had severe stress and my body was locking up, trying to save me."

Looking back on the experience, Sanford said she suspects she had a kind of temporary psychosomatic paralysis, a rare but real symptom psychiatrists have linked to post-traumatic stress disorder, or PTSD, and secondary trauma.

Counselors of victims of the September 11, 2001, terrorist attacks have reported struggling with secondary trauma, as have investigators who deal with child abuse cases.

It's an unavoidable hazard of working as an interviewer of war crime victims.

'You don't want to lose it'

Daniel Rothenberg was conducting interviews in Guatemala and dating Sanford. The two met at a human rights conference in Washington and he went to Guatemala on a Fulbright scholarship.

He remembers driving his girlfriend to an acupuncturist, encouraging her to sleep and take a break from the interviews. He took care of her until her paralysis eased. Neither of them contemplated quitting. When she was better, they both went back to interviewing full-time.

Rothenberg, in his late 20s then, is now an Arizona State law professor with a couple decades of interviews under his belt in Latin America, Asia and the Middle East. He recently assisted the completion of more than 9,000 interviews of Iraqis -- mostly men -- who say they were raped and tortured under Saddam Hussein's regime and after the U.S.-led invasion.

The accounts, recorded over five years, are contained in the online database "Iraq History Project," run by DePaul University's International Human Rights Law Institute.

"Victoria had a terrible experience, but we all have some kind of trauma. We just process it in different ways," he said. "I don't think I express it overtly. I'm usually just constantly stressed about having the 'right' reaction to someone. You want to be emotive -- not a robot -- but you don't want to lose it in front of someone. They don't benefit from you breaking down."

Some interviewers said their work can feel like watching the saddest, most frightening film they've ever seen and trying not to react.

He's come up with his own guidelines through the years of how to conduct interviews:

Start with an open question: Tell me about your experience. Look them in the eye. Don't look at your notepad. If they say, "No, I don't want to talk," then leave. If they say, "Yes," and tell you horrible things, wipe the emotion from your face. Get over being surprised they would tell a stranger, you, such intimate violations.

Know they are telling you because they need to tell someone, for whatever reason. And bearing that in mind, make no promises. Different victims want different things -- revenge, financial compensation, asylum, prosecution of their attackers. Tell them that you can only listen, and do only that.

Crying jags and sleepless nights

Sometimes, interviewers say, the feeling of helplessness as an observer is overwhelming.

Kurda Daloye, an international law scholar who speaks English and Arabic, has interviewed hundreds of victims of torture for the Iraq History Project.

It took only one interview with an Iraqi rape victim for Daloye, also an Iraqi, to decide she never wanted to interview another rape victim again.

The woman told Daloye she had been raped by a member of Saddam Hussein's Ba'ath Party. The woman had become pregnant and tried to hide the pregnancy. When she gave birth, the man who assaulted her showed up and snatched the child from her arms. The woman told Daloye she had no idea where to find her baby.

"I am a mother and I'm an Iraqi woman -- you know they kill you for this in our culture, having been made impure. I feel from hearing that single story too upset," she said from her home in Kurdistan.

As she recounted the story, Daloye wept.

"I am good at my job. I listen to so many crimes that happen to people, horrible things, torture, all the time. But this woman, she is different to me."

Daloye said she felt as if she was floating out of her body during the interview. She recalled looking at herself crying.

"I think of it as a movie. I want to think of it as something that was not really what happened," she said. "That way, I feel less bad about not being able to control myself. My tears were coming like someone (poured) water on me.

"We cried together, and from that, she knew that I really felt what she felt," she said.

When asked about secondary trauma, most interviewers said they didn't care for the term, that it's too anesthetized.

Instead, they said, talk about the crying jags and sleepless nights, the interviewers who get drunk every night but get up at 5 a.m. to do their work, and do it well. Talk about the quiet, cautious ones who keep their passionate, spontaneous colleagues from charging into situations that could be deadly. Mention the medical professionals who do this work for a pittance compared to the money they could make at a private hospital in a peaceful country.

Let everyone know that within the circle of interviewers are the natural den mothers, usually with children and families back wherever home is. They are the ones who make it seem all right to feel terrible.

Talk, they said, to Jan Pfundheller.

Groundbreaking moment

Pfundheller is not an easy woman to find. Two days of online searching yielded a single picture of a woman wearing khaki pants and a sensible haircut, her back to the camera, talking to a group of African refugees.

She looks like she could be the woman in front of you in the grocery store checkout line. And maybe she has been, since she's a grandmother from Brewster, Washington.

Her colleagues across the world, though, regard Pfundheller as one of the most erudite interviewers of rape victims in war zones.

"People ask me, 'Do you cry?' Well, of course I cry, but I do it in private, or at night. I'm pretty shattered at night," she said. "I'm grateful every time my heart is broken or I'm upset by what I've heard because I know I still have my own humanity speaking to me."

Pfundheller speaks in careful, low, controlled tones. There's something calming about her voice. It's this voice that rape and abuse victims in Brewster heard when Pfundheller worked there for years as a sex crimes detective.

Freshly retired from the police department in the mid-1990s, Pfundheller was at home when her husband, then a federal narcotics agent, announced that an exciting offer had come their way.

"He said there was a call from some international folks. They were looking for people to go to Kosovo to interview people who've been raped as part of the war there," Pfundheller recalled. "He asked me, 'Do you want to go together?' "

There wasn't much hesitation.

When she arrived in Kosovo on behalf of the International Criminal Court in The Hague and began to talk to the women, she felt overwhelmed. She heard how security forces entered homes, raped women in front of their families and abducted and raped young girls. Women were rounded up and kept as sex slaves in abandoned hospitals, barns or houses.

"It was especially difficult for me because I came from a place where the police helped people," Pfundheller said. "(If) you had a problem, you went to a police officer. In my world, the military protected borders. In this world, the police drank beer and watched other police officers rape a woman. Hearing these stories felt like a betrayal of everything I understood."

Pfundheller conducted interviews in Kosovo for four years. The stories she documented helped convict several Serb leaders of rape during The Hague tribunals in the late 1990s, according to Northwestern University law professor John Hagan.

Hagan worked on the pivotal case known as Foca, the territory in the Balkans where Serb soldiers used abandoned hospitals and other buildings to keep Muslim women and girls as sex slaves.

"Jan's work was invaluable," said Hagan. It showed that Serbs raped for three reasons: to inflict pain, to impregnate and "cleanse" the ethnic Muslim population, and to uproot them.

"You didn't have to rape someone directly to make them feel threatened," he said. "If you went into their villages and said, 'We're going to start raping all your women unless you move,' the villagers will leave their homes very fast and never come back."

The Foca case was a groundbreaking moment in international law.

Though systematic rape has been a part of conflicts from biblical times to modern-day wars, no defendant had ever been convicted specifically of rape as a war crime until then.

After The Hague tribunals ended, Pfundheller thought she should take a breather. She went home and tried to relax for a few months. It didn't work. "Turns out, I really don't like golf," she joked.

She got another assignment soon, this time to Darfur. In the span of a year working for the U.S. State Department, Pfundheller and her team of investigators collected thousands of stories from women and girls who said they -- and sometimes their babies -- had been raped, tortured and mutilated by Sudanese government-backed militias called Janjaweed, an Arabic colloquialism for "a man with a gun on a horse." The Janjaweed were targeting tribespeople who lived in villages where anti-government rebels took refuge.

When she accepted the job, Pfundheller felt prepared to face another Kosovo. What she found in Darfur left her without words. All she could do was report what she heard. The result contributed to then-Secretary of State Colin Powell acknowledging in 2004, for the first time, that genocide was happening in Darfur.

'Grace and comfort'

Pfundheller said interviewers shouldn't get caught up imagining that their work will change anything. In the case of Darfur, years of atrocities were documented before the international community acknowledged that genocide was occurring. And the violence there continues, despite Darfur becoming a kind of Hollywood cause célèbre.

"I believe that the world reacts according to what the world thinks it can do," she said. "With Darfur, it is just overwhelming to most people."

Pfundheller said she carries no naive hopes with her, only details of certain stories. There is a particular woman she met in a refugee camp in Darfur who stands out. Pfundheller tells the story like this:

"The woman's village had been overrun by Janjaweed. She was speaking in her native tongue. I had a translator. She was gracious. We sat together.

"She said her family was murdered. She saw other women being raped. Then she was raped. She was mutilated. She was physically mutilated at the end of the rape. She had been trained in nursing techniques outside of Darfur and crawled to other people to help them and to help herself.

"She was living in the most dire circumstances in a refugee camp.

"She was so gracious during her interview.

"When I'm at the end of an interview, I always tell my translator not to play psychologist, don't try and tell a person it will be OK. Just say, 'Thank you.' I remember I said to her, 'Thank you. I'm so sorry this happened to you, just thank you so much for telling me.'

"As I waited for it to be translated back to her, she said,

'No, thank you, my sister,' in perfect English."

Pfundheller was stunned. This woman could have kept the interview brief, reduced the pain of retelling her story, by simply talking directly to Pfundheller. Instead, she played by this interviewer's rules, out of deference and respect for Pfundheller and her process.

Recalling the moment, Pfundheller breaks down briefly, takes a breath and continues.

"I remember what she wore, her hair, the look in her eye. It's been a long time ago, but I remember everything about her.

"She was so dignified in this incredibly hot, dirty, smelly, horrible refugee camp. And she waited with patience and respect for me to finish my work, to reveal to me the circumstances of how she came to be across from me."

After she left the woman, Pfundheller said, she returned to her car with her translator, put her head in her hands and sobbed.

"I do try to give myself some grace and comfort," Pfundheller said. "You have to say I did the best I could have done.

"I did my best."

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