By Eric Hoover and Beckie Supiano

Before his first college-admissions interview this winter, Robert Johns was nervous. He looked over some tips provided by his counselors, at Saint Christopher's School, in Richmond, Va. He made sure to look presentable: collared shirt, necktie, khaki pants, nice shoes. The interview, at Washington and Lee University, went well. "It sort of flowed like a conversation," Mr. Johns says. He felt good.

Still, he wondered, had he messed up?

What admissions officers and students take away from interviews is murky. Nonetheless, the ritual endures, an intimate reminder of the time before stealth applications. In theory, admissions interviews add color, fleshing out the two-dimensional students whom admissions officials see in high-school transcripts, test scores, and writing samples.

Interviews remain a celebrated tradition at some of the nation's most prominent institutions. Over the past decade, several colleges have made them a central component of their admissions operations—an investment of considerable time and money. And one of the nation's most selective universities is considering the possibility of offering them for the first time.

After all, their appeal is evident. For applicants, interviews offer a way to learn about colleges as they try to find the right fit. It's also a chance for students to impress those who will evaluate their applications. And it's a way for applicants to demonstrate interest in a college, which may help their chances of admission.

And colleges, which put students through an ever more electronic process, relish the chance to reach out and show prospective students that the admissions office wants to know them as people.

Moreover, the interview is an opportunity for the college to sell itself. As enrollment outcomes become harder to predict, the interview is a potentially powerful tool for increasing "yield," the percentage of admitted students who enroll at a given college.

Roughly two-thirds of colleges attribute at least "some importance" to admissions interviews, according to data from the National Association for College Admission Counseling. In general, such interviews are most frequently used at highly selective colleges, particularly small ones, which enroll only a fraction of the nation's students. At many large institutions, it would be logistically impossible to offer interviews to everyone. Some admissions offices don't do interviews, simply because they consider them a waste of time. Even among colleges that do invite applicants to sit down and talk, most advertise such conversations as optional. So it's a safe bet that a majority of college applicants never participate in a single admissions interview.

But Mr. Johns, who had admissions interviews at two colleges, cites one benefit of those conversations. They were the only moments during the application process when he was able to get feedback from colleges. And he believes those talks helped him to do something important: "Become a face," he says, "and not just a name."

'The Myth of Expertise'

In the professional realm, interviews are notoriously slippery endeavors. Research has shown that people tend to make snap judgments about other human beings, and that those judgments may not tell them anything important, such as what kind of employee someone will be. Interviewers are prone to the "halo effect," the tendency to see a positive trait in an interviewee and to ignore negative ones (or to seize upon a negative trait and then ignore positive ones). In other words, subjectivity has its downsides, one of which is that we tend to have gut reactions to other people.

Scott E. Highhouse, a professor of psychology at Bowling Green State University, has studied the enduring popularity of the traditional, unstructured interview in employment settings. "They are so unreliable that the absence of validity is almost assured," he says.

In a 2008 article in Industrial and Organizational Psychology, Mr. Highhouse explained that while people may like to think that they can predict human behavior, actually doing so is difficult. He also explained the "myth of expertise" in hiring: the belief that, with time and experience, people can become skilled in making intuitive determinations of an applicant's potential for success. "There is no evidence that some interviewers are better than others," he says.

That critique goes to the heart of admissions work, which hinges on the assumption that special, qualified individuals can make better predictions about applicants' potential than others can. At many colleges, those predictions are based on more than just grades and test scores. They are also based on judgments about facts, context, and characteristics not found in those measures.

If the informal, get-to-know-you interview is not likely to reveal anything more than what standardized tests of intelligence and personality do, are all interviews worthless? Not necessarily. They can be structured in ways that enhance their validity and reliability, Mr. Highhouse explains. The trick is that such standardized interviews require time and training. And in practice, they may seem less like a conversation, and therefore less "natural."

William E. Sedlacek, a professor emeritus of education at the University of Maryland at College Park, agrees with at least some of Mr. Highhouse's conclusions about interviews. "Any two people doing them won't agree very well," he says. "Without a lot of training, interviews will give you a scatter-gun kind of assessment."

Mr. Sedlacek is an expert on noncognitive traits, which, he believes, can and should be considered in admissions. He has advised several colleges and universities on ways to incorporate noncognitive variables into their evaluations of applicants. But without proper training, he says, an interview won't necessarily help a college meet a stated enrollment goal, such as increasing the diversity of its applicant pool.

For one thing, an interview might end up serving the strengths of some students but not others. "It depends on what you're interviewing for," he says. "If that's sort of vague, it will just give you a watered-down version of what the SAT gives you, benefiting verbally bright, upper-middle-class people who really know how to do this kind of thing better."

One-on-One Admissions

Two years ago, Wake Forest University started encouraging applicants—strongly—to schedule interviews. The move coincided with Wake Forest's decision to make the ACT and SAT optional for all applicants, a change that it hoped would increase the number of nonwhite applicants.

So far the change has been a success, says Martha B. Allman, Wake Forest's director of admissions. The university's applicant pool has grown larger and more diverse, and interviews have changed the way the office operates. "I'm not sure how we made decisions before we did this," she says.

At Wake Forest, interviews do not follow a rote format; admissions officials are free to ask different questions of different applicants. That's something Ms. Allman considers crucial, for it allows her staff members to tailor their questions to each applicant's experiences and interests. "It's helped me learn how to better appreciate differences between students," she says.

There are some common questions, though. This year applicants were asked to describe the most intellectually stimulating class they took in high school, what they would say if they had 15 minutes alone with President Obama, and what they would do if they had a "do over" button.

Each interview was rated on a 1-to-7 scale, but that score did not have numerical weight in an applicant's overall evaluation. Instead it became relevant only in discussions of applicants teetering between acceptance and rejection. "Often it tipped the scales," Ms. Allman says. "In difficult cases in committee, if interviews were very, very good, or very, very bad, it would become more of a factor."

On the back end of the process, Ms. Allman and her colleagues try to account for differences among students, including the fact that some students are simply more poised and confident than others. They also talk a lot about the halo effect.

"I tell them to ask themselves not whether this is a person they would like to invite to a dinner party, but to ask whether they would be an asset to a class," Ms. Allman says.

This year about half of Wake Forest's 10,500 applicants sat for face-to-face interviews. Most of the rest completed short, timed essays online. About 500 participated in remote interviews via Skype. That's a labor-intensive proposition, one that has changed the dynamics of admissions work on the campus. During the summer, admissions-staff members might find themselves conducting a half-dozen interviews per day.

Tom Willoughby knows all about those challenges. As vice chancellor for enrollment at the University of Denver, he has seen his applicant pool swell over the past decade, since the university started requiring interviews of each and every applicant. That was challenging enough when Denver got 4,000 to 5,000 applications a year, but when the number surpassed 10,000 recently, the university had to change its policy. "It became overwhelming," Mr. Willoughby says.

Now interviews are optional, but they remain popular with students. This year about half of the 12,000 applicants did interviews with Denver, which offered the opportunity in 30 cities. Those who sit for the interviews, the university has found, are twice as likely to enroll as those who do not. That is valuable information, helping to justify the cost of conducting interviews throughout the nation. Mr. Willoughby estimates that the program has cost the university as much as $200,000 per year.

Denver's applicants are usually interviewed by a faculty member or admissions officer (or both), as well as by an alumnus. The meetings take place in hotels, where as many as six teams might conduct 10 to 12 interviews per day for two or three days. At the end of each day, the team reaches a consensus about whether each student would be a good fit. By design, the evaluators do not know other information about the student's application.

The interviewers write up summaries, which can be blunt. Some might say that a student's answers lacked depth, or that a student didn't seem all that interested in Denver. After one interview, Mr. Willoughby recalls writing: "This student was totally absent."

Some students are dazzling, however. This year, Mr. Willoughby interviewed one young woman in Phoenix. When she left, he and his colleagues were speechless. She expressed such a passion for learning that they stopped taking notes and just listened.

As at Wake Forest, the interviews do not factor into applicants' evaluations at Denver, but they inform the inevitable debates about students on the margin. "No doubt this has helped us when we're really torn about what to do," Mr. Willoughby says. "It's those cases where we have 500 applicants, and we only have 150 seats left."

All in all, the interviews have been a tool that has helped Denver raise its profile. For one thing, they tend to impress parents. "It's good applicant relations," he says.

'A Way to Be Engaged'

The same principle applies to alumni. Denver's interview program provides a way for the university to engage its graduates. That is also true for Tufts University.

Amy R. Spitalnick is a volunteer alumni interviewer for Tufts. She usually suggests Starbucks as the venue, because it's a comfortable location for a high schooler. She offers to buy them coffee; the process can be stressful for interviewees, and she figures it's the least she can do. Ms. Spitalnick does not take many notes, hoping to keep the students calm. Later, she will write a few paragraphs and submit them on Tufts's online system. She tries to give each applicant the same consideration she would want in their shoes. But Ms. Spitalnick also knows firsthand that the interview counts for only so much—she never had one herself, and still got in.

The Tufts Alumni Admissions Program provides "a way to be engaged as an alum beyond just happy hours," she says. A 2008 graduate employed by J Street, a pro-Israel, pro-peace organization in Washington, Ms. Spitalnick worked in Tufts's admissions office as an undergraduate. She is co-chair of the alumni program's Washington area committee.

Her fellow alumni have a lot of "Tufts enthusiasm," Ms. Spitalnick says. "It's cheesy, and we're overeager." The interviews are a way for younger alumni, who can't necessarily make big donations, to give back, she says. Down the road, as their salaries grow, seeing the quality of Tufts applicants could inspire them to break out the checkbook.

Tufts has an extensive, formal interview program, says Matthew Hyde, who runs the alumni-admissions operation. Out of 15,000 applicants, 12,000 request interviews, and about 8,500 have them. Applicants get to show another side of themselves to the university, and alumni get to sell Tufts. "It's a yield moment for us," says Mr. Hyde, associate director of admissions.

That interviews are meant to increase a college's yield is clear to Jon Reider, director of college counseling at San Francisco University High School. He tells his students that after a certain point, the interview will turn into the interviewer's trying to sell them on the college. At that point, he says, they should "smile and be gracious and say how interesting that is."

That's not to say that interviews serve no purpose in admissions decisions. But their degree of importance at any one college is irrelevant, Mr. Reider says, because he'd give applicants the same advice: Ask thoughtful questions. Look the interviewer in the eye. Be on time. Don't wear flip-flops. In the end, he says, interviews are a way for applicants to be seen, and anything that gives them that chance is good.

That said, interviewers are human, and some of them are not very good.

The problem can be worse when interviews are conducted by alumni, who are, after all, volunteers rather than professionals. Many high-school counselors have heard tales, secondhand if not first, of alumni interviewers' behaving badly. Michael Greshko, a student at Providence Day School, in Charlotte, N.C., had one interviewer who tried to engage him in a political argument. Mr. Greshko was unfazed but did appreciate having the opportunity to send in an evaluation of the interviewer to the college.

Some students and counselors, however, prefer alumni interviews to those conducted by admissions-staff members. Alumni can share their personal stories about a college, and if they are relatively young, their experiences won't be too far removed from what the student might find on the campus. Alumni, who are not college employees, can come off as being more genuine, too.

Besides, alumni interviewers are usually given only basic information about the applicants, and not their test scores or grades, while someone on the admissions staff may have already read each student's whole file. That means the alumni interviewer can walk in with fresh eyes and "play a cleansing role," says Patrick J. O'Connor, director of college counseling at the Roeper School, in Birmingham, Mich.

Counselors' and families' main concern about interviews, though, is not knowing how they are used, which can vary greatly from college to college. A small grass-roots organization is hoping to add some clarity in that regard.

The group is the New England Coordinators of Alumni Admissions Programs, led by Kathy Strand, associate director of admissions at Simmons College, and Mr. Hyde, of Tufts. The group, which has its next meeting in June, is developing a statement of best practices for alumni interviews. In particular, Ms. Strand says, it is considering interview locations, the importance of training alumni volunteers, and the transparency of the interview process.

Weighing Options

In the past, Stanford University has not conducted admissions interviews, in contrast to many of its competitors. Stanford applicants have sometimes been taken aback that they are not asked to interview. But the university is considering a new approach: It is trying out an interview program in certain parts of the country.

"We want to see if we can approach it with equity and manage it effectively," says Richard H. Shaw, dean of admissions and financial aid. Mr. Shaw, previously at Yale University, had experience with interviews there. "My own opinion is they can be helpful. In the vast majority of cases, they are neutral." An interview will not usually change an applicant's score, though it might. Normally, he says, what it adds is "texture."

At Stanford, not having admissions interviews had made the university's process seem unique, and so there has been some resistance to changing that. But Mr. Shaw decided to go ahead with the pilot because interviews put "a human touch on a process that's pretty large."

The university plans to make a decision about whether to include interviews as part of the process nationally in May 2011. "If the university and my colleagues decide they don't want to do it, fine," says Mr. Shaw. "If they choose to do it, that's a lot of work."

A lot of work that will not necessarily provide a measurable result. Christine L. Pluta, who used to work in the University of Pennsylvania's admissions office, recalls taking interview summaries with a grain of salt. "They were only occasionally useful," she says, "because most of the reports were generally positive. People tend to be sympathetic toward young people."

Ms. Pluta, now director of college counseling at the Lycée Français, a private school in New York, believes that interviews are more useful for increasing yield than as a way to distinguish one applicant from another. As for students, she believes that the experience of speaking in front of an admissions representative can be beneficial, but that applicants tend not to know what to make of interviews. "Most of them go in scared," she says, "and come out confused."