On a muggy Saturday morning last summer, the Koussevitzky Music Shed at Tanglewood was humming with people. The Boston Symphony Orchestra followed conductor James Levine through a contemporary overture commissioned for his debut season in Boston. Several minutes into the piece, Levine, dressed as casually as his picnicking audience in a polo shirt and slacks, swiveled to face the crowd and beckoned to an audience member. An energetic gray-haired man darted toward the stage from his seat in the cordoned-off front section. While he and Levine carried on an emphatic but inaudible discussion, a crescendo of murmurs rose from the audience. Whispers of “Who is that?” met the knowing reply, “That’s John Harbison – the composer.”

John Harbison, the composer of Darkbloom: Overture for an Imagined Opera, the piece being rehearsed that Saturday morning, won the Pulitzer Prize in 1987 for his cantata The Flight into Egypt. He’s a conductor, a performer, and a sometime poet who writes the librettos for his operas. John Harbison is also an Institute Professor at MIT.

There are only 15 Institute Professors, and they are regarded as the very best among an already impressive crowd. The highest honor awarded to MIT faculty, appointment as an Institute Professor is at once an acknowledgment of extraordinary leadership, accomplishment, and service and an invitation to follow intellectual pursuits without the hindrances of departmental responsibilities. Institute Professors report directly to the provost, rather than to a department head, and they have no obligation to teach, which opens the door to projects and political appointments that would otherwise not be feasible.

The process of selecting a new Institute Professor is arduous, thorough, and conducted entirely behind closed doors. It begins with a nomination from fellow faculty members, which is then evaluated by an ad hoc committee appointed by the chair of the faculty and the president, comprising faculty members from various departments and several people from outside MIT. The case is ultimately presented to the executive committee of the MIT Corporation for approval. Only when the process is complete – and only if the appointment succeeds – is the candidate even informed that he or she was nominated.

The title of Institute Professor is unique in that it’s not part of the normal promotion sequence of assistant professor, associate professor, and full professor. “It’s not the aspiration of everybody,” says Rafael Bras ‘72, SM ‘74, ScD ‘75, who has participated in the Institute Professor selection process in his capacity as chair of the faculty. “It is an honor and a distinction that your peers give you in recognition of what is, even among that group, extraordinary accomplishment.”

The current group of Institute Professors includes three Nobel laureates, four Heinz Award recipients, a former director of the CIA, and a former secretary of the air force. They are an invaluable resource for MIT, and the president makes good use of their expertise at biannual lunches during which she can ask their advice on anything from national politics to university policy. “We have a tremendous group of people who have been in Washington and who have had major administrative positions at MIT,” says Joel Moses, PhD ‘67, an Institute Professor in electrical engineering and computer science, “and we enjoy giving advice.”

“Most of us have been here for a long time,” adds Mildred Dresselhaus HM, an Institute Professor with a joint appointment in physics and electrical engineering, “and we have a real commitment to science policy and, much more generally, to MIT.” Fulfilling that commitment to MIT, however, can sometimes entail commitments elsewhere. John Harbison spends his summers attending music festivals. Summer festivals play an important role in shaping the lives of young musicians, says Jean Rife, a lecturer in the music department, because they bring together people and ideas from all over the world. Harbison’s presence at festivals enriches not only the experience of those who attend but also the musical culture back at MIT. Harbison “brings a connection to the larger world of music, so we’re not small-time here. There’s a sophistication that he brings,” says Rife, who has worked with Harbison for more than three decades.

Harbison is popular at Tanglewood, where he directed a five-day festival last summer and spent several weeks coaching musicians and giving lectures. He can hardly walk ten feet without encountering an admiring student or a colleague eager to offer compliments or discuss a stylistic point from the rehearsal that’s still fresh in everyone’s ears. His energy and his curiosity about music seem endless as he darts around the Tanglewood campus in the Berkshires, visiting one rehearsal or concert after another. A performance of Prokofiev’s Romeo and Juliet by high-school students elicits the same concentrated gaze and armchair conducting as the BSO’s performance of his own piece.

But Harbison’s enthusiasm isn’t just a summer fling; his passion for music is never missing in the classroom. What he enjoys most about teaching at MIT is the school’s emphasis on innovation, which he says is critical to the vitality of an art like classical music. “There’s a great respect for forward movement and for people to make things at MIT,” he says. And the students have a level of intensity and excitement that he says is hard to find, even at conservatories. MIT students aren’t studying music to become professional musicians; they’re doing it because they love music. And Harbison has no trouble keeping up, says Rife: “He brings the same energy he takes out to the rest of the world when he comes back to school.”

Collegial praise for the Institute Professors flows freely. A casual mention of Mildred “Millie” Dresselhaus, for example, is almost always paired with a flattering parenthetical: “Millie Dresselhaus – superwoman.” “Millie Dresselhaus – she’s amazing.” Or “Millie – she’s a powerhouse.” “She’s just done amazingly innovative things in so many areas,” says Raymond Ashoori, a professor of physics. “She’s been president of every society that you can mention, and at the same time, I find her to be very patient with people and very supportive of people,” he says.

Dresselhaus’s personal style seems incongruous with her track record as a high-powered physics professor who helped push the frontiers for women in science. Dressed in an old-fashioned skirt and blouse, with her gray hair pulled back in a braided bun, she has a calm, humble manner.

Dresselhaus came to MIT in 1960 as a staff scientist at Lincoln Laboratory. When she arrived, there were only a handful of female tenured professors at the Institute, but she says she never felt at a disadvantage. “I know you’re thinking that we had a hard time when we came here,” she says, “but that’s not at all true. We were very well accepted for what we were doing.”

And she was doing a lot: she’s one of the nation’s leading experts in carbon science and has done groundbreaking research in thermoelectricity and superconductivity. In recent years, she headed a nationwide U.S. Department of Energy study on hydrogen production, storage, and use; the findings have kept her at the forefront of the global quest for sustainable energy sources.

Although women were well accepted when Dresselhaus arrived at MIT, in the United States there were still far fewer women in science and engineering fields than men. For more than three decades, Dresselhaus has been instrumental in promoting opportunities for women in science. She was awarded the Carnegie Foundation grant in 1973 to encourage women to study and seek careers in traditionally male-dominated disciplines, and for many years she held the Abby Rockefeller Mauze chair – a professorship endowed in support of women in science and engineering.

She made efforts to create additional on-campus housing for women, which helped balance enrollment and, as a result, evened out admissions requirements. (The scarcity of housing had made it tougher for women to gain admission.) She started the Women’s Forum, in which female faculty and staff convene to discuss issues of concern; and she created an undergraduate mentoring course that featured guest speakers who often spoke about overcoming obstacles.

For more than 20 years, Dresselhaus has had an appointment at MIT that doesn’t require her to teach; nevertheless, she continued teaching until 2003. Her office is piled high with stacks of papers – a state she attributes to her three books in progress – and her shelves are lined with three-dimensional crystal-structure models interspersed with statuettes and other “toys” that her students have given her. “I’ve had a lot of students here, and they are like my children,” she says. “I like to have their things strewn around the place; it’s kind of nice.”

It’s not uncommon for Institute Professors to continue teaching after their selection or to return to teaching later in life after illustrious careers in science and politics. One wall of John Deutch’s office is arrayed with photographs: Deutch shaking hands with five former presidents; Deutch arm in arm with Bill Clinton. An energy bill he helped pass is displayed like a diploma. Deutch is a former director of the CIA; he’s held a series of positions in the U.S. Departments of Energy and Defense since the 1970s. He’s an overseer of the Museum of Fine Arts in Boston. At MIT, he has served as chairman of the Department of Chemistry, dean of science, and provost. But first and foremost, he says, he’s a professor.

Deutch ‘61, PhD ‘66, joined the MIT faculty in 1970. By 1977, he had begun to establish ties to Washington, serving as the first director of energy research in the new U.S. Department of Energy.

“Energy has fundamentally been my first love,” he says. “It combines all the elements that really interest me: science, engineering, public policy, international affairs.” In addition to conducting basic research in physical chemistry, Deutch publishes articles on energy policy, examining topics from nuclear proliferation to fuel cells and hybrid cars.

“He’s one of the guys who understands technology and who knows the government and who knows what the government cares about,” says Nurettin Demirdoven, PhD ‘03, SM ‘05, who earned his doctorate in technology and policy and had Deutch as an advisor. “He’s really successful in what he does because he can put these two things in the same packet….I think his contributions mostly originate from putting science in a way that people in the government understand.”

Deutch is famously stern and straightforward. Ask him about his political career, and he returns curt, tempered responses, as if he has answered the questions a thousand times. But ask him about tennis, and his eyes light up. His voice gets louder and sounds younger, and he’ll even lean back in his chair and smile. Get him to talk about his family, and his usually narrow gaze and firm voice relax; suddenly warm and affable, he talks as if to an old friend.

“My wife plays beautiful tennis,” he muses. “It’s one of the great joys of my marriage, playing mixed doubles.” Deutch doesn’t count his political appointments or intellectual attainments among the “big deals” in his life. “You want to know the truth?” he asks. “I have two grandsons on the way this summer. I have three sons. That’s a big deal. That’s what happens when you get older – you start to count your real blessings.”

And these days he seems to prefer professorship to politics. “My satisfaction comes from being an MIT professor,” he says. “Whether I have a named chair, or whether I’m an Institute Professor, to me, is a minor matter compared to the pleasure and privilege I enjoy as an MIT professor.”

While the appointment of Institute Professors might seem likely to excite envy, it actually appears to build camaraderie. Moses, who was head of the Department of Electrical Engineering and Computer Science when Dresselhaus was named Institute Professor in 1985, says, “It was an enormously uplifting event for the department. It isn’t simply about the individual – there’s also the feeling that the department has been honored.”

MIT is rife with extraordinary people, and limiting the number of Institute Professors to only a dozen or so means that many exceptional teachers and researchers are left out. But that’s part of what makes the title so meaningful. “In general, I think we’re maybe a little more tough on ourselves than we should be,” says Moses. But selecting the Institute Professors, he continues, “is one of the things that MIT does well.”