Behavioral interview

Ask for an event, not a promise

A behavioural question asks what happened in a particular situation, rather than what the person thinks they would do. For example: “Tell me about a time you had to change a plan after receiving difficult feedback. What did you do?” The answer can reveal the person’s account of their actions, choices, and result.

This is a question approach, not the opposite of a structured interview. OPM distinguishes behavioural questions about relevant past experience from situational questions about a hypothetical response; both can appear in a structured method.

The STAR method from the interviewer’s chair

Situation, Task, Action, and Result are the four parts of the STAR method. The UK National Careers Service explains it to job seekers. For an interviewer it does a different job: it tells you which part of an answer is still missing.

The OPM Structured Interview Guide, published in September 2008, builds those parts into the question. Each behavioural question should draw out the situation, task or context, the actions the person took or did not take, and the impact of those actions. Superlatives such as “the most difficult” or “the last time” help the candidate settle on one specific incident.

The guide’s sample probes follow the same sequence:

• Situation: “What factors led up to the situation?”
• Action: “How did you respond?” and “What is the first thing you did?”
• Outcome: “What was the outcome?” and “Is there anything you would have said and/or done differently?”

Decide before the first interview which probes are allowed for each question. OPM asks for very similar probes across candidates: the wording can follow what a person said, the meaning should not change. When “we” runs through an answer, a probe on the Action step (“what did you do yourself?”) separates the person’s contribution from the team’s.

Scoring against the criterion

STAR is not a scoring instrument. A candidate does not need to tell a polished four-part story to provide relevant evidence, and a fluent story does not establish competence on its own.

Score each answer against the competency the question was written for. In OPM’s method, subject-matter experts write example behaviours for each proficiency level of each question, and interviewers use them as a general guide rather than an absolute. The rating follows straight after the interview, from notes that record what the candidate actually said, so each score can point to the example behind it.

Choose the evidence the role needs

Write each question around a competency that matters for the role, then decide what follow-up would make answers comparable. A past example is one source of evidence. For a skill that needs to be demonstrated directly, a work sample may answer a different question better.

Use the same underlying criterion for all candidates in the role. That preserves the difference between listening for an example and rewarding the person who presents one most smoothly.