Viewpoint: There Are No 'Holy Grail' Interview Questions, but There Are Some Good 'Commandments'

Human resource managers have long looked for the "Holy Grail" of interview questions—that is, a set of inquiries that are most insightful and can predict which job applicant will be the best employee—on job-search websites and in popular articles. However, the search for these Holy Grail questions is likely to be fruitless. 

As the adventurers in "Monty Python and the Holy Grail" discovered, the grail can't be found (no matter how many French castles or Internet sites you visit). We suggest HR professionals and hiring managers stop searching for Holy Grail interview questions. Instead, here are a few "commandments" (i.e., guidelines) to conduct high-quality interviews.

First, thou shalt gather information about the job(s). Good interviewers begin by learning about the job in question. Look at the job description and talk to subject matter experts (SMEs), such as current employees in the job and their direct supervisors. The goal of these conversations is to obtain a list of the important behaviors that constitute strong job performance. This effort is not as daunting as it may appear. We've found it fun to talk with SMEs, and most SMEs like telling you about their job.

Tip: Identify the behaviors that constitute great and poor performance in each job for which you are interviewing by asking SMEs questions like, "What do great performers do in this job, and what do poor performers do?" or "What are the key parts of this job?"

Second, thou shalt focus on questions that predict job performance. Tom Janz, a well-known interviewing consultant, said, "Past behavior is the best predictor of future behavior." This means you should ask about specific occasions where the job applicant has engaged in certain behavior. For example, if following procedures is an important behavior for the job, a behavioral question might be "Tell me about the most recent time you had to make a decision about how to follow procedures." The key issue here is to focus on what people have done in the past to see what they are likely to do in the future. 

Truly behavioral questions don't involve several commonly used types of questions, such as "Tell me about yourself," "What are your strengths?" and "What are your weaknesses?" These are much too general and don't necessarily relate to behaviors on the job. Behavioral questions also don't involve probing for personality or philosophies, and they aren't "goofy" questions such as "If you opened your refrigerator and saw a penguin, what would you say?" Nor do they involve "brain teasers," such as "How many golf balls fit in a football stadium?" None of these questions are likely to be a Holy Grail since they don't have a proven track record of predicting who will best perform the job.

Tip: Behaviors don't have to come from the job to predict job performance. For example, you might tell college students or people re-entering the workforce that their examples can be from courses or volunteer activities that seem similar to the work environment. The key issue is the behavior.

Third, thou shalt structure the interview. Essentially, this means to standardize the interview as much as possible for all applicants. The single best way to do this is to ask the same questions of everyone. This gives all the applicants the same chance to demonstrate their qualifications in the interview. Put simply, this is the fairest approach you can take and results in better information for your evaluation.

The good news is that the first three commandments will "predestine" you to have a legally defensible interview. When an interview is based on understanding the nature of work in the job, and the questions are about job performance behaviors, then everyone gets the same chance to demonstrate their qualifications. Thus, one can argue every question is logically job-related. It also minimizes the chances for discrimination claims because everyone was treated similarly. This is especially true for "excessive subjectivity" lawsuits where the plaintiff's attorney argues that a) interviewers could ask anything they wanted to ask and b) they will seek to hire people similar to themselves (e.g., white males). Research has clearly shown that these issues are largely mitigated or eliminated with structured interviews.

Tip: Avoid the temptation to have a free-wheeling interview to assess generic "fit," such as liking the applicant's personality. Concepts like personality don't predict who will be a better employee.

Fourth, thou shalt use the interview to gather new information. This means collecting information that's unique and allows for an in-depth analysis of past behaviors, with one instance for each question.

Many interviewers are tempted to start the interview by going through the applicant's resume. Yet this often defeats the intent of focusing on job-related questions based on information from SMEs. In fact, this approach allows some applicants to be treated differently than others and might open up the organization to allegations of discrimination.  

Some experts suggest that interviewers only ask questions that can be quantitatively answered. For example, "How many math courses did you take in college?" "What was your grade point average in your major?" They believe only these kinds of questions can eliminate racial or gender biases. However, these questions likely will not provide sufficient information to reveal the best candidates. Further, evidence suggests this approach is, at best, not necessary. At worst, it's a waste of your time because you could obtain this information from transcripts.

Tip: Realize that predicting the future behavior of someone you don't know is very difficult. Stay humble by recognizing no one can do this perfectly, and use your limited time in the interview wisely.

Fifth, thou shalt map the questions onto the behaviors. That is, there should be an inventory of the important behaviors that constitute the job. Then, each interview question should be clearly aimed at (or mapped onto) one of those behaviors. This step helps make sure each important behavior is covered and no one behavior is overemphasized, and the mapping can be used to show the careful construction of the interview process.

Tip: List the important job behaviors in the left column of a document. List the interview questions in the right column and draw an arrow to the behaviors that each interview question is designed to cover.

Constructing a high-quality interview is hard but rewarding work. There are no quick fixes because there are no Holy Grail interview questions. Instead, there are good commandments that can greatly help us choose the best employees. The commandments emphasize learning about the nature of the work by talking to SMEs, asking high-quality questions, structuring the interview and gathering new information. We should also map how the questions relate to job performance before conducting an interview. 

Following these commandments will give you the greatest chance of finding the best employees. 

Philip L. Roth, Ph.D., is a professor in the management department within the Powers College of Business at Clemson University. John D. Arnold, Ph.D., is a professor in the management department within the Robert J. Trulaske, Sr., College of Business at the University of Missouri.