Chapter 11: Delivering a Competency Based Interview
The STAR structure
Competency based interviews ask you to evidence specific behaviours through real examples, usually introduced with phrases such as tell me about a time when. The most reliable way to structure an answer is STAR: Situation, Task, Action, Result. Set out the context briefly, explain what you specifically needed to achieve, describe the action you personally took, and close with the measurable result.
The most common failure is spending too long on the situation and too little on the action and result, which are the parts that actually demonstrate your capability. Aim to spend around twenty per cent of your answer on situation and task combined, and the remaining eighty per cent on what you personally did and what happened as a result.
In practice: Elena's conflict resolution
Asked to describe a time she managed conflict within a team, Elena answered: a project was six weeks behind schedule and two senior team members disagreed publicly on the cause, which was affecting morale across the wider team. I needed to resolve the disagreement quickly and get the project back on track without undermining either person. I met with each individually to understand their position, then brought them together with a shared, data led view of the schedule slippage, focusing the conversation on the plan forward rather than blame. The project recovered its schedule within four weeks, and both team members later asked to work together again on the next phase.
In practice: Kwame's influence without authority
Asked about a time he had to influence without authority, Kwame answered: a new reporting process I believed was necessary sat outside my direct remit, and the team that owned it had no bandwidth to prioritise it. I needed their buy in without being able to instruct them directly. I built a short business case showing the hours the current process was costing across the wider department each month, and proposed a pilot with one team rather than asking for a full rollout commitment upfront. The pilot team adopted it within two weeks, and the wider rollout followed within the quarter, based on their own results rather than my argument alone.
In practice: Louisa's honest failure
Asked to describe a time she had failed, a question many candidates fear more than any other, Louisa answered: I underestimated the time a system migration would take and gave a delivery date to stakeholders that turned out to be unrealistic, which damaged confidence in the project when we missed it. I needed to rebuild that confidence and reset expectations honestly. I went back to stakeholders early, before the deadline arrived, with a clear explanation of what had been underestimated and a revised, more rigorously tested timeline, rather than waiting until the date had passed. The project completed against the revised date with no further slippage, and two stakeholders later told me the early, honest reset was what kept their confidence in the wider team intact. Choosing a genuine failure, rather than a disguised strength, and showing what changed afterwards, is usually more persuasive than trying to avoid the question's intent.
- Spending most of the answer describing the situation and leaving little time for the action and result.
- Describing what a team did collectively rather than what you personally did.
- Choosing an example with no clear, measurable result.
- Failing to prepare examples in advance and improvising under pressure.
- Prepare five to six STAR examples covering leadership, conflict, failure, achievement and change.
- Write each one down in full before condensing it into a spoken answer of around ninety seconds.
- Practise delivering each example out loud until it sounds natural rather than rehearsed.
- Check each example ends with a clear, specific result, not a vague summary.
This programme gives you frameworks and actions. Your coach is where they become genuinely yours. Rather than arriving with answers, consider bringing these open questions into your next session and exploring them together:
- Which of your stories are you proudest of, and why do you tell it less often than the others?
- What does the story you keep avoiding say about you?