Definition
The competency-based interview (or behavioural interview) rests on a simple principle: the best indication of how someone will act is how they acted in a comparable situation. Questions start with "Tell me about a time when..." and target a specific competency of the role: handling conflict, prioritizing, persuading a client.
The STAR method helps structure and probe the answer: Situation, Task, Action, Result. The recruiter follows up on the candidate's own action ("what did you do, personally?") and on the result achieved.
Best practices
It works best inside a structured interview: the same questions for everyone and scoring with an interview scorecard. Choose the competencies during the intake meeting, and accept examples from other contexts (volunteering, school, another industry): it is the competency you assess, not the title. For soft skills, see our article on evaluating soft skills.
Concrete example
To assess prioritization, the recruiter asks: 'Tell me about a week when you had more work than time.' He follows up on what the candidate chose to postpone and why, then scores the answer against the scorecard. The follow-up questions are what separate a rehearsed answer from a real one.