Competency-based interview questions and how to answer them

A competency-based question asks you to describe a real situation from your past in which you showed a particular skill or behaviour. They are easy to spot, because they almost always start the same way: "Tell me about a time when…", "Give me an example of…" or "Describe a situation where…". The idea behind them is simple. How you handled something before is the best evidence an interviewer has of how you will handle it again.

They are used widely in the UK, and especially in the public sector and in large organisations, because they make interviews fairer to compare. Each candidate is asked the same questions, and the panel scores each answer against a set of indicators for that competency: what a strong answer shows, and what a weak one lacks. You are not being judged on charm. You are being judged on whether your example contains the evidence they are listening for.

• Some employers call them behavioural questions, or describe the interview as structured. The approach is the same.
• The Civil Service assesses "behaviours" as part of its Success Profiles framework. A behaviour question is a competency question in all but name.
• A hypothetical question, "What would you do if…", is a different thing. It asks for your judgement, not your history, so answer it as a plan.

Panels rarely invent competencies on the day. They take them from the same documents you applied against, so you can predict most of the interview before you walk in. Read the job description and, if there is one, the person specification, and list every skill or behaviour that is described as essential. Then look for the employer's own framework: many publish their values or behaviours on their careers pages, and some name the ones they will assess in the interview invitation itself.

1. List the essential skills and behaviours from the job description and person specification.
2. Add any values or behaviours the employer publishes, or names in the invitation.
3. Group the list into five to eight competencies, such as teamwork, communication or leadership.
4. Expect a question on each, and more than one on whatever the advert stresses most.

The wording changes from employer to employer, but the competencies themselves repeat across most roles and sectors. These are the ones that come up most, with the shape the questions usually take. Use them to test your bank of examples, not as a script: if you have no good answer to one of these for a competency the advert lists, that is the gap to fill first.

• Teamwork: "Tell me about a time you worked with others to achieve something you could not have done alone."
• Communication: "Give an example of when you had to explain something complicated to someone without your background."
• Problem-solving: "Describe a problem you solved where the answer was not obvious at the start."
• Handling conflict: "Tell me about a time you disagreed with a colleague. What happened?"
• Working under pressure: "Give an example of when you had several urgent things to do at once. How did you decide what came first?"
• Adapting to change: "Describe a time when your plans changed at short notice."
• Leadership: "Tell me about a time you had to get people to follow a decision they did not agree with."
• Service: "Give an example of when you went beyond what was expected for a customer, patient or colleague."
• Learning from mistakes: "Tell me about a time something you were responsible for went wrong."

Leadership questions are not only for managers. Leading a piece of work, persuading a group or taking charge when something went wrong all count, at any level.

STAR is the structure most panels expect, and some interviewers will name it. It stands for Situation, Task, Action and Result, and it keeps an answer from wandering. The common mistake is spending too long on the background. The panel is scoring your action and its result, so that is where most of your time should go.

1. Situation: one or two sentences of context, such as where you were and what was going on.
2. Task: what you specifically had to do, or the problem that was yours to solve.
3. Action: what you did, step by step, and why. This is the heart of the answer.
4. Result: what changed because of it, with a measure if you have one, and what you would keep or change next time.

Say "I", not "we". Panels need to know what you did, and an answer full of "we" leaves them guessing whether you led the work or watched it. Aim to finish in about two minutes, then stop: if they want more, they will ask a follow-up, and follow-ups such as "What would you do differently?" are part of the scoring too.

You do not need a separate story for every possible question. You need a bank of strong, true examples, each of which can answer several. A project that went wrong and was rescued might show problem-solving, working under pressure and handling conflict, depending on which part you tell. Write each one down in STAR form, then mark which competencies it covers, and check that every competency on your list has at least one good example.

• Prefer recent examples. A story from the last two or three years is easier to tell in detail and carries more weight.
• Use examples from outside work when they are your best evidence: volunteering, study, caring or running a club all count.
• Include at least one example of something that went wrong and what you learned from it. Someone with no failures sounds untested, not perfect.
• Use each story once per interview, if you can. Repeating the same example for every question makes your experience look thin.
• Never invent or borrow an example. Follow-up questions go into detail, and a story that is not yours falls apart there.