Dialling for Proof: How to Test a Consultant's Record by Telephone

Most consultants arrive at a pitch with a case study. It is well designed, carefully anonymised and, almost without exception, ends in a successful outcome. None of that makes it dishonest. It simply makes it marketing. When the decision carries real weight — a systems migration, an operational turnaround, a regulatory matter with a deadline attached — the more informative exercise is a short telephone call with someone who has already paid the invoice.

A reference supplied by the consultant is a floor, not a ceiling. It tells you that at least one engagement ended well enough for the client to agree to be named. What it cannot tell you is how the work felt from the inside, where it nearly came off the rails, or whether the last three months were as calm as the final report suggests. Six questions, asked in roughly twenty minutes, will get you most of the way there.

1. How did the engagement begin, and what did you expect?

Start before the work started. Ask the referee what problem they thought they were buying a solution to, and whether the consultant's first proposal matched it. Listen for the gap between the original brief and what was eventually delivered. A modest gap is normal and often healthy. A brief that quietly doubled in size, with no conversation about cost, is worth noting.

It is also worth asking how the consultant behaved before the contract was signed. Were they willing to say that a piece of work was not needed? Did they push back on an unrealistic timetable? A referee who remembers being told 'you do not need me for that' is describing an adviser rather than a supplier.

2. Where did the scope change, and who suggested it?

Scope creep rarely announces itself. It arrives as a small extra analysis, a further workshop, an additional stakeholder to interview. Ask the referee where the brief moved and whether any change was documented and priced before the work was done. You are listening for two things: whether change was controlled, and whether the consultant was honest about what the change would cost.

3. How did you hear about problems, and how quickly?

Good news travels through the final report. Bad news is the test of a working relationship. Ask the referee to recall a moment when something went wrong or a deadline slipped, and how they found out. Was it raised early, in plain language, with options attached? Or did it surface at the steering meeting once it could no longer be concealed?

A useful follow-up is to ask who their day-to-day contact actually was. In larger firms, the partner who wins the work is not always the person who does it. Confirm that the individuals promised in the pitch were the ones on the call.

4. What did you receive on the last day?

Handover is where consultancy is most often quietly disappointing. Ask what arrived when the team left: a report and nothing else, or working files, documented assumptions, access to systems, a trained internal owner and a session to walk through it all. Then ask the sharper question — could somebody else pick this up next week without calling the consultant?

5. Tell me about the weakest part of the work.

This is the question that sorts a rehearsed reference from a candid one. A short pause followed by a specific, measured criticism is a good sign. So is a referee who can describe a disagreement and how it was resolved. Be wary of an answer that lists no weaknesses at all; it usually means either the referee is being polite or the relationship was too shallow to generate friction.

6. Would you use them again, and for what exactly?

A warm 'absolutely' is pleasant but uninformative. The better answer is conditional: 'yes, for the data work, but I would not use them for change management'. Specificity is credibility. If the consultant is a generalist, ask which part of the engagement the referee would hand them again.

Reading the answers carefully

References are usually chosen with care, and referees are usually inclined to be kind. There are a few patterns worth noticing.

• Identical phrasing across calls. If two referees use the same sentence about 'a really collaborative approach', you may be hearing a script rather than a memory.
• No client who ended badly. Ask directly whether any engagement in the last three years was terminated early or not renewed, and whether you can speak to that client. A consultant with a clean record over a long period is possible; a consultant who will not discuss a difficult ending is telling you something.
• Friendly witnesses. A referee who is also a current supplier, a former colleague or a personal friend is not useless, but they are not independent. Ask how they came to know the consultant.
• The consultant on the line. Politely decline. A reference call should be a private conversation.

Guarded answers need interpreting rather than dismissing. A referee who says 'I cannot discuss the commercial detail' is behaving properly. A referee who cannot describe how the consultant communicated, or who becomes vague when asked about handover, is not.

Before you dial

Ask for three referees rather than one, spanning different types of work and different years. Check the firm's record at Companies House — filing history, accounts, any change of name — and confirm that professional indemnity cover is in place for the coming year. Write down what you want to know before the call, and make a short note afterwards, while the tone of the answers is still fresh.

The purpose of all this is not to catch anyone out. It is to replace a polished narrative with a second, independent account of how the same work was experienced. Two accounts that broadly agree, including about the difficult parts, are worth more than any number of case studies.