How Do I Interview Someone for a Job I've Never Done?

You know what is going wrong in the business, but you have never done the job that might fix it. A candidate can sound convincing for an hour while you remain unsure whether their approach would work.

Split the assessment into what you can judge as the owner and what needs a qualified specialist's review. You can explain the problem, constraints and decisions the role will own. You should not pretend that a list of technical interview questions makes you qualified to assess every answer.

This guide is about designing that assessment. If you need help deciding what a first marketing hire should own, use the marketing-role guide. If the specific issue is evaluating AI use, use the AI-skills checking exercise.

Write the outcome before the technical questions

Consider a fictional wholesaler hiring its first inventory specialist. The owner knows that customers are promised items that turn out to be unavailable. Staff spend time reconciling the shelf count with the sales system. The owner does not know whether the right fix involves forecasting, receiving procedures or system configuration.

A useful brief might say:

Find where stock records stop matching physical stock. Establish a reviewable process for recording movements and handling discrepancies. Recommend changes within the agreed budget, explaining risks and what evidence would show improvement.

That describes a problem and responsibility without pretending to know the solution. Add the systems in use, available data, staffing constraints and decisions that need approval.

OPM's job-analysis guidance connects tasks with the competencies required to perform them. The practical question is which parts of this job need specialist knowledge, and how you will obtain credible evidence of that knowledge.

Use two complementary lines of questioning

The owner can ask the candidate to explain their work in terms the business can inspect:

• What would you need to establish before recommending a change?
• What did you personally own in a comparable situation?
• Which constraints changed your approach?
• What would make you stop, escalate or revise the plan?
• What would we be able to review after the first stage?

These questions explore reasoning, scope and communication. A clear answer is useful, but not proof of technical correctness. An expert may explain an incorrect approach fluently; another may need a follow-up question to make a sound approach understandable.

A suitable specialist should assess the parts you cannot reliably judge: whether the proposed method is technically appropriate, what material risks it misses, and whether the candidate's claimed responsibility is supported by their explanation.

Give the reviewer a job—not an unrestricted veto

Look for someone with relevant practical experience in the kind of work and operating environment involved. Check potential conflicts, including an interest in selling their own services instead of helping you hire. Agree the scope, fee, confidentiality and handling of applicant material before sharing it.

Here is a short reviewer brief you can adapt:

Business problem and role responsibility:
Environment, tools and constraints:
Competencies required on entry:
What the owner will assess:
What needs your specialist assessment:

Evidence you will review:
Same core questions/task for each candidate:
How findings should be recorded:
- Supported capability
- Concern, with the evidence behind it
- Unknown and the follow-up needed

Conflicts disclosed:
Confidentiality and data-access arrangements:
Scope, fee and decision deadline:

Ask for reasons you can understand and check. “Not senior enough” is not a complete finding. “Could describe the reporting dashboard but could not explain how stock adjustments were authorised” identifies something the next conversation can investigate.

Keep the final hiring decision with the responsible people in the business. The reviewer supplies evidence and specialist judgment; they do not silently redefine your vacancy.

Use a small fictional case with enough context

For the wholesaler, a discussion case could show a simplified purchase receipt, sales record and stock adjustment that disagree. Ask what the candidate would check next and why. Do not require access to real customer data or ask them to solve your entire operation as unpaid application work.

The specialist should review the case and evaluation criteria before candidates see it. Without that review, the owner may accidentally write a puzzle with missing information, an incorrect answer key or no connection to the actual job.

State the task, time expectation, permitted tools and assessment conditions in advance. Check applicable rules and accessibility needs. Use comparable conditions and relevant follow-up questions rather than making each candidate navigate a different surprise test.

The fictional case is an interview aid, not a validated predictor of future performance. If the work requires formal credentials, licences or checks, a good case discussion does not replace them.

Resolve disagreements at the evidence level

Suppose you liked the candidate's clear explanation, but the reviewer raises a material technical concern. Do not average “excellent communication” and “unsafe approach” into a reassuring overall score. Ask which requirement is affected, what evidence supports the concern and whether a focused follow-up can resolve it.

The two-reviewer disagreement guide helps separate disagreements about the job from disagreements about the evidence. If the reviewer is criticising a skill the role does not require, revisit the brief. If the concern is essential, do not dismiss it because the conversation felt good.

An AI-generated answer key can also be wrong. Use AI to help organise questions or notes if appropriate, but not as your only technical authority. Resume Ranker can provide a starting review of PDF resumes against your brief; it cannot certify unfamiliar specialist competence for you.

You do not need to become the expert before hiring one. You need a clear business brief, a credible way to assess the specialist work, and a record of what remains unknown before you decide.