Beyond the Courtesy Call: Interrogating a Consultant's References Properly

Every UK buyer of consulting services knows the ritual. Shortlist drawn up, proposals compared, and then — somewhere before the contract lands with the legal team — a reference call or two, conducted in the spirit of a formality rather than an inquiry. Fifteen minutes, a few courteous questions, and a glowing verdict that was never really in doubt.

The trouble is that a reference call designed to confirm a decision tells you almost nothing. The one designed to stress-test it can tell you a great deal — provided you ask the questions that polite conversation avoids.

Why Most Reference Checks Fail

The standard script — Were you happy with the work? Would you hire them again? — invites only one possible answer. No former client, particularly one who may want to work with the consultant again, is going to volunteer criticism on request. British reticence does the rest. What you receive is an endorsement manufactured by the structure of the conversation itself.

There is also a selection problem. The consultant chooses which references to offer, and naturally offers the engagements that ended well. The client whose project stalled, or who quietly declined to renew, is never on the list. Your job is not simply to take the references given, but to reconstruct the fuller picture around them.

Ask About the Wobble, Not the Win

The most revealing information lies not in the highlights but in the friction. Every engagement of any substance encounters a moment where the work goes off script: a deadline slips, a recommendation is challenged, the data proves awkward. How a consultant behaved in that moment matters far more than anything they delivered when conditions were favourable.

So replace the happy questions with forensic ones:

• "Tell me about a point where the engagement didn't go to plan. What happened, and what did they do?" — This single question does more work than any other. Listen for specifics. A vague answer suggests there is either nothing to tell or something being withheld.
• "What did you pay for that you didn't end up using?" — Scope creep and padding are endemic. A buyer who feels they got value will answer this easily; a buyer who doesn't will hesitate.
• "Who internally pushed back hardest, and how did the consultant handle them?" — Resistance is normal in any organisation. The question is whether the consultant engaged with dissent or simply routed around it.
• "What changed in your business six months after they left?" — This separates work that embedded from work that evaporated. A reference who can name a lasting change is worth ten who can only recall a pleasant final presentation.
• "If you had the engagement again, what would you specify differently?" — This invites the reference to criticise the brief rather than the consultant, which is precisely why it works. The answer often surfaces the weaknesses neither party would state directly.

Find the References They Didn't Offer

Where possible, speak to someone adjacent to the engagement rather than the named sponsor. The finance director who processed the invoices, the operations lead whose team had to live with the recommendations, the internal analyst who worked alongside the consultant day to day — these people saw the unvarnished version. A short message via LinkedIn, framed honestly (I'm considering hiring X and doing due diligence), is rarely refused and frequently illuminating.

For public sector or larger private engagements, procurement records, framework reviews and even Companies House filings can add context about the consultant's track record and stability that no curated reference list will.

Listen for the Gaps

On the call itself, pay attention to what is not said. Hesitation before answering the question about things going wrong. Enthusiasm about the person but vagueness about the outcomes. Praise for communication skills offered in place of evidence of results. These are not damning in themselves, but patterns across two or three calls are instructive.

And take notes on language. A reference who says "they were lovely to have around" has told you about hospitality, not capability. One who says "the board still uses the framework they built" has told you something you can act on.

A Short Protocol for Procurement Teams

For those running a structured process, a workable discipline looks like this:

1. Request three references, at least one from an engagement that was not an unqualified success — and notice how the request is received.
2. Speak to at least one person not on the list.
3. Ask each reference the five questions above, in that order.
4. Record answers verbatim where possible; impressions fade and soften.
5. Compare notes across references within 48 hours, while the discrepancies are still visible.

None of this requires hostility or mistrust. The best consultants welcome rigorous due diligence because they have nothing to hide and know it distinguishes them from the pack. Indeed, how a candidate responds to a searching reference request is itself a data point — defensiveness before the contract is signed is a reliable preview of defensiveness afterwards.

The reference call is one of the few moments in a buying process where you hear from people with no incentive to flatter you and every reason to be candid, if only someone asks properly. Treat it as the audit it should be, not the courtesy it usually is, and you will enter the engagement with your eyes open — which is, in the end, the entire point of due diligence.