Unstructured interviews are wildly ineffective at predicting future performance. Yet casual conversations, gut instinct and feelings are the ubiquitous means for assessing talent in today’s competitive marketplace, even at the highest levels of the Fortune 500.

In fact, over the past several years as an executive search consultant, only two clients, prior to working with us, had interview processes in place that were deliberately designed to limit natural biases and intuition. Instead, the overwhelming majority leverage the unsophisticated and futile assessment methods of generations past: laissez-faire conversations, brain teasers, work experiences and references.

The reasons for adopting such archaic approaches are multifold. First, most hiring managers and recruitment professionals have never experienced or been taught a better way. Applying a more standardized approach could be seen as minimizing the autonomy of the interviewer. Most of us think we’re great at interviewing, so we don’t see a need for change on that front. And many companies often view rigorous interview methods as antithetical to their friendly and inviting culture — they’re afraid to scare a top candidate away.

Science has the answers to these conundrums. Indeed, the evidence is overwhelming: Other than work samples and cognitive ability (IQ) tests, structured interviews are far and away the best means for predicting the future performance of your candidates.

The challenge, then, is how to begin implementing this proven yet unfamiliar process. The good news is that it’s not as complicated as it might sound. Here are four steps to get you started:

Summarize What Candidates Can Expect

As the candidate enters the room, ensure unplanned small talk is kept to a minimum. Any improvised forays into one’s personal interests can unconsciously lead to biases early on in the process. Instead, warmly introduce yourself, define the role, list the key competencies and explain how the interview questions will be structured. Be sure to let them know how long the interview will last, how many questions you’ll be asking and how you’ll be scoring each candidate. Also, point out that you’ll be taking notes so they don’t get distracted by it after a tough question.

Inform interviewees that the reason for such formality is to ensure every candidate has the same experience. If there are no questions on process, it’s time to begin.

Ask the Same Job-Related Questions in the Same Order

Because you’re hiring for a well-defined role, determine which competencies are the most critical for success. Then, draft seven to 10 thought-provoking, open-ended questions that test for these attributes.

For example, to test for one’s ability to persuade and build unanimity among stakeholders, the interviewers might first ask a broad question: “Tell me about a time you had to use your presentation skills to influence someone’s opinion.” Dive deeper with follow-up questions: “How did you prepare for the presentation?” “What was the desired outcome, and what points did you emphasize to drive home your proposition?” “What was the result?” “What did you learn from that experience, and what could you have done differently?”

To ensure consistency throughout each candidate’s experience, it’s imperative that both the baseline questions and the follow-up questions are preplanned and delivered in the same order.

Maintain Consistent Interviewers and Clearly Defined Rating Scales

Naturally, no interviewer rates the same way. Despite every attempt to minimize biases, we’re all susceptible to unconscious influences. In order to ensure that each candidate is scored equitably, there should be a consistent set of interviewers. Ideally, there should be no more than four interviews in total, and interviews should be conducted by a well-trained and diverse group of colleagues: a peer, a boss, a subordinate and a cross-functional neutral party.

Interviewers should rate candidate responses using a cohesive scale. For example, at my executive search firm, we use a rating scale of 1 to 5. The ratings represent “awareness,” “basic,” “intermediate,” “advanced” and “expert,” respectively.

But it’s not enough to simply give each level a general label. You should also leverage existing subject-matter experts in that role — or the hiring manager if it’s a new position — to define what specific behaviors should be displayed at each level.

For instance, if you’re assessing the candidate’s ability to empathize with a broad set of stakeholders, you might define “awareness” as “occasionally attempts to create a safe environment for asking questions and sharing outcomes.” A score of 5, or “expert,” on the other hand, might be defined as “considers the needs and emotions of others and the constraints of the circumstances when considering a course of action.”

The key is specificity. The clearer you are in defining ideal behaviors at each level, the less ambiguity and variance the interviewers will face.

Rate Candidates Immediately After Interviews

Many of us can’t remember what we did yesterday. How much more difficult is it to recall a detailed response to an interview question hours after it was given? It’s nearly impossible!

This is why it’s important that interviewers score candidates immediately after they leave the room. In your notes on each question, be sure to include actual examples given by the candidate and why that justified their final score. These notes will be crucial for discussing candidates — and breaking any ties between them.

Finally, each interviewer should give final scores to all candidates, and the candidate with the top scores among the four interviewers should be selected.

That’s it! This simple, structured interviewing approach will revolutionize your ability to predict the future performance of your next hire. Plus, because each candidate feels like he or she is on equal playing ground throughout the assessment process, his or her overall experience with your brand will improve and your Net Promoter Scores will soar.