Paul E. Farmer is no stranger to the spotlight, but seeing his life set out in 336 frank pages was more than he had bargained for.

The world-renowned Harvard Medical School infectious disease specialist had spent parts of three years with Pulitzer Prize-winning author Tracy Kidder ’67 by his side. Now, with Kidder’s book on the verge of release, he wasn’t sure he liked what he saw.

“When I read the manuscript and told him I felt a bit over-exposed, [Kidder] expressed a bit of genuine sympathy with my predicament but did not offer to change anything,” Farmer writes in an e-mail.

Farmer’s intense, personal and sometimes combative relationship with Kidder had begun nearly a decade earlier with a chance meeting in Haiti, where Farmer operates a free medical clinic he founded in the mid-eighties. Kidder was researching an article on American military presence in the troubled island nation.

By 1999, Kidder was conducting interviews for a New Yorker profile of the outspoken doctor—and soon was shadowing Farmer on his daily routine of healing and advocating for the world’s destitute.

Kidder has just published the results in Mountains Beyond Mountains: The Quest of Dr. Paul Farmer, A Man Who Would Cure the World—an account as challenging as it is edifying. His latest non-fiction book is really two works in one: alongside the litany of Farmer’s achievements, recited with his usual eye for detail, Kidder unflinchingly explores the moral and emotional complexity surrounding the book’s creation.

His previous books—including House and The Soul of a New Machine—have won him the highest accolades, including a Pulitzer Prize for Soul. But from the project’s inception, Kidder says, he realized that Mountains Beyond Mountains would differ from his acclaimed portraits of urban schoolteachers, small-town police officers and house-builders.

“I don’t mean to diss any of the subjects I’ve put my little efforts into, but this is clearly the most important subject I’ve ever written about,” Kidder says.

Farmer is an impossibly busy man: an influential medical fundraiser, a sharp critic of U.S. policy towards the developing world and a practicing physician with his feet in what seems like a thousand clinics at once. He splits his time between regular rounds at Boston’s Brigham and Women’s Hospital and the free medical complex he founded in Cange, a rural settlement in the most impoverished part of Haiti.

In between, he teaches courses at the Medical School, where he is a professor of medical anthropology, and stops by to supervise healthcare programs run in seven countries by Partners in Health (PIH), the non-profit medical organization he co-founded in 1987.

For months, Kidder compiled interviews on Farmer’s life and work, filling page after page with what he calls “compulsive” notes on the process. Kidder accompanied Farmer on innumerable red-eye flights and hiked to house-calls in the Haitian countryside, staining his notes with sweat. “Frankly, I’ve lost count of the times I went to Haiti,” Kidder says. In January of 2000, Farmer recalls, the author spent the full month with him, “pretty much 24/7.”

As a result, Mountains Beyond Mountains is much more than a reserved journalistic account of Farmer’s career in medicine and public policy. When Kidder writes of Farmer’s ceaseless push for a “preferential option for the poor,” for equity in health care and for the eradication of HIV/AIDS and drug-resistant tuberculosis, he also tells of his own thoughts on Farmer—both personally and professionally. While all but one of Kidder’s previous books have been written in the third person, Mountains Beyond Mountains has lengthy first-person narrative portions, and Kidder is a vocal character throughout.

“I very quickly realized that I’d have to tell a bit of the story of my relationship with Paul,” Kidder says.

He explains that he did this in part to ground the stranger-than-fiction events chronicled in the book.

“There’s a pervasive cynicism out there that I knew I’d be fighting against,” Kidder says. “I knew you needed a first-person narrator to tell you this is true…it’s this idea of having an everyman who’s much less virtuous than Farmer to bear witness to the fact that this guy’s real…It’s not enough to just say, oh, well it happened and therefore I can just set it down.”