Interview questions for problem solving: 14 questions from defining the problem to making the fix stick
On this page
- What does problem solving look like in observable behavior?
- Which behavioral questions show how a candidate solves problems?
- Which situational questions work for candidates with less experience?
- How do you adapt the questions for hands-on troubleshooting roles?
- What can you lawfully ask, and what should you avoid?
- What do strong and weak answers sound like?
- How do you score problem solving on a 1–4 scale?
- What mistakes do interviewers make with problem solving?
- Questions people ask
Interview questions for problem solving should take a candidate through one real problem from start to finish: how they noticed it, how they defined it, how they found the cause, which fix they chose and tested, and how they made sure it stayed fixed. The most useful single question is "Tell me about a problem you solved that stayed solved. How do you know?", because it separates people who diagnose causes from people who patch symptoms and move on. Below are fourteen questions, ten behavioral in four stages and four situational, each with what a strong answer contains, red flags and a follow-up probe, plus a talk-through format for hands-on troubleshooting roles, the lawful limits, sample answers and a 1–4 anchored scale.
Several neighbors cover parts of the same ground. How to interview for problem solving uses a live case to watch someone reason in real time; use it alongside these questions, not instead of them. Critical thinking covers checking whether information deserves to be trusted, decision making covers choosing between options, and systems thinking covers causes that cross team boundaries. This page is the question bank for the whole loop, with most weight on the two stages that candidates skip in their stories: diagnosis and follow-through.
What does problem solving look like in observable behavior?
Definition: problem solving is getting from a situation that is not working to one that is, and keeping it that way: stating the problem precisely, finding its cause, choosing a fix in proportion to the problem, checking that the fix worked and preventing a repeat. O*NET, the occupational database published by the U.S. Department of Labor, describes the related skill of complex problem solving as identifying problems, reviewing related information, and developing, evaluating and implementing solutions (O*NET OnLine, 2026). Its level examples run from laying out tools to complete a job to planning emergency relief for a major metropolitan area, a useful reminder to match your questions to the size of problem the role really handles. Listen for five behaviors:
- Defining before solving. Says what is wrong, for whom, since when and how big, before proposing anything.
- Diagnosing the cause. Gathers evidence, tests explanations in a sensible order and separates the symptom from the cause.
- A fix in proportion. Contains the damage first when needed, then chooses a permanent fix whose cost fits the problem.
- Checking and preventing. Measures whether the fix worked, checks again later and changes whatever let the problem happen.
- Escalating at the right point. Recognizes when a problem is beyond their skill or authority and hands it on with a clear summary of what was tried.
Which behavioral questions show how a candidate solves problems?
Ask for one specific problem and stay with it. The first telling is usually tidy; the probes are where the score comes from. The ten questions are grouped by stage, so you can choose the two or three stages that matter most for the role.
Defining the problem
| Question | A strong answer contains | Red flags | Follow-up probe |
|---|---|---|---|
| 1. Tell me about a problem you were asked to solve that turned out to be a different problem. | Noticed the request described a symptom or a pre-chosen solution, went back to the person and agreed what actually needed to change. | Delivered exactly what was asked, although it did not help. | "What did you ask that changed the definition?" |
| 2. Describe a time you had to work out how big a problem really was before deciding what to do. | Counted or measured it against a baseline, found who was affected and sized the effort to match. | Acted on one complaint or one loud voice. | "What fact told you it was worth fixing?" |
| 3. Tell me about a problem that several people described differently. | Collected each account, separated what was observed from what was assumed and agreed one statement of the problem. | Took the most senior person's version. | "Whose version turned out closest, and why?" |
Finding the cause
| Question | A strong answer contains | Red flags | Follow-up probe |
|---|---|---|---|
| 4. Walk me through the hardest problem to diagnose you have dealt with. What did you check first, and why? | Possible causes ranked by likelihood and by how cheap they were to check, then ruled out one at a time. | Tried fixes at random until something worked. | "What did you rule out, and how?" |
| 5. Tell me about a time your first explanation for a problem was wrong. | What they believed, the evidence that contradicted it and how quickly they changed course. | Has never been wrong, or kept the first fix because it "sort of worked". | "What told you it was wrong?" |
| 6. Tell me about a problem you had to see, reproduce or test yourself before you understood it. | Went to where the work happens, watched it fail or ran a small test, and found something the reports had missed. | Relied only on secondhand descriptions. | "What did you see that the reports did not say?" |
Choosing and testing a fix
| Question | A strong answer contains | Red flags | Follow-up probe |
|---|---|---|---|
| 7. Tell me about a problem where you had to limit the damage before you could fix the cause. | Contained it quickly, told the people affected, then went back to the cause instead of treating containment as the end. | Stopped at the workaround and moved on. | "How long passed between the containment and the real fix?" |
| 8. Describe a fix that did not work the first time. What did you do next? | Worked out whether the diagnosis or the execution was wrong, adjusted, and tried again with a way to tell whether it worked. | Blamed the users, or repeated the same fix harder. | "Was it the diagnosis or the fix that was wrong?" |
Making it stick
| Question | A strong answer contains | Red flags | Follow-up probe |
|---|---|---|---|
| 9. Tell me about a problem you solved that stayed solved. How do you know? | A measure before and after, a check weeks later, and a change to the process, standard or training that removed the cause. | "Nobody complained after that." No check and no measure. | "When did you last check?" |
| 10. Describe a problem you could not solve yourself. When and how did you hand it on? | Recognized the limit early, escalated with what was known, tried and ruled out, and stayed involved. | Struggled alone for weeks, or escalated with nothing but "it's broken". | "What did you include when you handed it over?" |
Questions 4, 5 and 9 do the most work. Diagnosis and verification are the parts of problem solving that a confident story can leave out, and the probes on those three questions bring them back.
Which situational questions work for candidates with less experience?
For early-career candidates, or when the behavioral examples are thin, use scenarios close to your own work. Listen for the same stages in the answer: define, diagnose, contain, fix, check.
-
"Customers have started calling about late deliveries. Your manager says, 'Fix it.' What do you do in the first two days?"
Probes: What would you want to know first? What would you do while you find out? -
"A tool your team depends on fails a few times a week at random. The vendor says it is user error. What do you do?"
Probes: How would you test the vendor's explanation? What do you tell the team? -
"Two weeks after you fix a problem, it comes back in a slightly different form. What do you do?"
Probes: What does it tell you about your first fix? Who else would you involve? -
"You have spent a day on a problem and you are stuck. Your manager is busy, and a colleague solved something similar last year. What do you do?"
Probes: What would you bring to the colleague? When would you stop and escalate?
How do you adapt the questions for hands-on troubleshooting roles?
For technicians, IT support, maintenance and field service roles, problem solving is mostly troubleshooting, which O*NET defines as determining causes of operating errors and deciding what to do about it. A talk-through works better than a story: describe a real symptom from the job and ask the candidate what they would check, in what order, and what would make them stop and call someone. Use the same symptom for every candidate for the role. The symptoms below are examples; replace them with ones from your own work.
| Role | Example symptom to describe | A strong talk-through includes |
|---|---|---|
| Maintenance technician | A conveyor stops a few times a shift and restarts on its own. | Makes the machine safe before touching it, asks operators when it happens, checks the simplest causes first and records what was found. |
| IT support | Several users cannot connect to the VPN since this morning. | Checks what the users have in common, whether anything changed overnight and whether it is one user or the whole service, and tells users what to expect. |
| HVAC technician | A rooftop unit runs, but the building is not cooling. | Confirms the complaint, checks settings and airflow before components, and explains the likely cause and cost to the customer. |
| Customer service lead | Refund requests have doubled this week. | Finds which products and channels, reads a sample of requests and checks for a recent change before blaming agents. |
For maintenance roles, listen for energy control before any diagnosis. OSHA's lockout/tagout standard, 29 CFR 1910.147, covers servicing and maintenance of machines where unexpected start-up or a release of stored energy could injure employees. A candidate who reaches for the machine first and thinks about safety second has told you something important, whatever their diagnostic skill.
What can you lawfully ask, and what should you avoid?
Problem-solving questions rarely cause legal trouble on their own. The risks come from the tests and exercises that often travel with them, and from examples that stray outside work. In the United States, as of November 2026:
- Keep scored tests job-related. Under Title VII's disparate impact provision, 42 U.S.C. 2000e-2(k), a practice that causes a disparate impact by race, color, religion, sex or national origin is unlawful unless the employer shows it is job related for the position and consistent with business necessity. A case built from the real work is easier to defend than a generic puzzle or aptitude test. If you score a test, review pass rates by group; the four-fifths rule page shows how.
- Offer accommodations for live exercises. The ADA, 42 U.S.C. 12112(b)(6) and (7), bars tests that screen out people with disabilities unless they are job related, and requires tests to be given so the results reflect the skill being measured rather than an impaired sensory, manual or speaking skill. Give the case in writing as well as aloud, and allow extra time on request; see ADA accommodations in interviews.
- Keep the problems at work. "Tell me about a problem you solved in your personal life" invites answers about health, family or money that you should not weigh. If a candidate volunteers them, steer back to work. Illegal interview questions covers the wider list.
This is general information, not legal advice. State and local laws can add requirements.
What do strong and weak answers sound like?
Illustrative answers to question 9, written to show the difference in structure. They are not from real candidates, and the numbers are examples.
Weak: "We had loads of errors on invoices, so I made a new template and trained everyone on it. After that it was much better, and my manager was really happy with it."
There is no definition of the problem, no cause, no measure and no later check. "Much better" is a feeling, and the template may have treated a symptom.
Strong: "Invoice disputes from one client group went from about one a week to four. I pulled the last twenty disputes, and fourteen had the same cause: missing purchase order numbers, because the client's buyers had changed their process and we were still invoicing the old way. The template was fine. I agreed with the client's accounts team that every order would arrive with the PO number in a fixed field, and we added a check that blocks an invoice without one. Disputes went back to about one a month. I checked again at three months and at six, and the same check is now part of onboarding for every new client."
The strong answer defines and sizes the problem, finds the cause from evidence, rejects the obvious fix, removes the cause, measures the result and checks it later.
How do you score problem solving on a 1–4 scale?
| Score | Anchor |
|---|---|
| 1 — No evidence | Jumps to a solution without defining the problem, cannot describe a cause, has no way of knowing whether fixes worked, or blames others when problems recur. |
| 2 — Limited | Fixes what is in front of them. Diagnosis is mostly trial and error, checks are informal, and escalation comes too late or with too little information. |
| 3 — Solid | Defines and sizes the problem with evidence, tests explanations in a sensible order, contains damage when needed, chooses a proportionate fix, verifies it with a measure and escalates with a clear summary. |
| 4 — Strong | Everything at 3, plus removes the conditions that caused the problem, changes a process or standard so it does not recur, revises their own diagnosis readily and helps others solve similar problems. |
If the candidate's best evidence is about questioning a number or a claim, score it under critical thinking; if it is about choosing between good options, score it under decision making. Keeping the evidence apart stops one strong story from inflating three scores.
What mistakes do interviewers make with problem solving?
- Scoring the solution instead of the diagnosis. A clever fix to the wrong cause is not good problem solving. Ask how they found the cause.
- Rewarding firefighting. A candidate with many stories of late-night rescues may work somewhere problems are never prevented. Ask what stopped the next one.
- Accepting "it was fixed". Ask how they know, and when they last checked.
- Using brainteasers. Puzzles measure puzzle practice. Use problems from the job.
- Penalizing escalation. Handing a problem on at the right time, with a good summary, is part of the skill.
- Writing "good problem solver" in the notes. Record the behavior: "sized the problem from 20 disputes, found missing PO numbers, added an invoice check, verified at three and six months."
Questions people ask
What are good interview questions to assess problem-solving skills?
Three questions cover most of the skill: 'Tell me about a problem you were asked to solve that turned out to be a different problem', 'Walk me through the hardest problem to diagnose you have dealt with', and 'Tell me about a problem you solved that stayed solved. How do you know?' Probe each one for evidence: what the candidate checked, what they ruled out and how they measured the result.
How do I assess problem solving for hourly or hands-on roles?
Use a talk-through instead of a story. Describe a real symptom from the job, such as a conveyor that stops a few times a shift, and ask the candidate what they would check, in what order, and when they would stop and call someone. Use the same symptom for every candidate, and in maintenance roles listen for safety steps before any diagnosis.
Is it a bad sign if a candidate escalated a problem instead of solving it?
Not on its own. Escalating at the right time, with a clear summary of what was known, what was tried and what was ruled out, is part of problem solving. The weak patterns are struggling alone for weeks before telling anyone, and escalating straight away with nothing but a description of the symptom.
How is problem solving different from critical thinking and decision making?
Problem solving is the whole loop, from noticing that something is wrong to checking that it stays fixed. Critical thinking is the checking inside that loop: questioning data, claims and assumptions. Decision making is the choice between options once they exist. Score them separately so that one good story does not raise all three.