How to write a consulting case study that wins clients

Prospective clients want proof that you’ve already solved a problem like theirs, ideally for an organisation that looks a lot like their own, and a case study gives them that far more convincingly than any description of your services, because it shows your thinking at work on a real situation.

Plenty of consultants put off writing them, because of confidentiality or because results feel hard to put into numbers. Both are solvable, and a modest, honest case study beats none.

What should a consulting case study include?

Three sections will do, with a title and a one-line summary on top.

The situation

Describe the client’s world before you turned up. Say what kind of organisation it was and how big, what the problem was, and why it mattered to them. Write it so that a similar prospect reads it and thinks “that’s us”. Two or three short paragraphs are plenty.

The approach

Explain what you did, in order, and why. This is where your expertise shows, so give the reasoning, not a bare task list. Mention how long it took and how you worked alongside the client’s team.

The result

Say what changed, and be specific. Include what the client would say changed, as well as any figures. If the results are still coming through, say so and describe what’s been achieved so far, because readers prefer an honest progress report to a story that pretends to be finished.

A fourth element often helps: a short quote from the client. It adds a human voice. Sceptical readers find it reassuring.

How do you get a client’s permission?

Ask early, ideally when you agree the engagement, and ask again near the end while the value is fresh in their mind. A clause about case studies in your terms makes the conversation easier, but you should still ask before anything is published.

1. Explain what you want to publish and where, whether that’s your website, proposals or LinkedIn.
2. Give them options: named, partly anonymised or fully anonymous.
3. Send the draft for approval and make whatever changes they ask for.
4. Get their approval in writing. Email is fine. Keep it.
5. If you later update it in a way that changes the content, tell them.

Written approval protects you both. The advertising regulator’s guidance on testimonials says marketers must hold documentary evidence that a testimonial is genuine, and that quotes mustn’t be edited in a misleading way. A client quote in your case study falls under the same thinking, so hang on to the original message.

How do you write a case study when the work is confidential?

Much consulting is sensitive, and some clients will never be named. You can still tell the story.

Start by anonymising the client: “a regional manufacturer with around 150 staff”, say, or “a professional services firm”. Blur the details that would identify them, such as the location or exact figures, while keeping the shape of the problem intact.

You can also combine lessons from several engagements into one story. Only do that if you state clearly that it’s a composite and not a single client. Never pass off an invented client as a real one. And check the confidentiality terms in your contract, along with anything you learned from the client’s own data. When in doubt, ask them.

An honestly labelled anonymous case study is credible. One that looks made up does more harm than having nothing.

How do you use numbers honestly in a case study?

Figures make results concrete. They also create risk if they overstate what you did.

Only use figures you can evidence from the client’s own records, and keep that evidence on file. Say what each number measures and over what period, and give the starting point. Don’t claim all the credit, either. If the client’s team, shifts in the market or other advisers played a part, write “contributed to” and avoid “delivered”.

Be careful not to suggest the result is typical. What happened for one client is no promise to the next. Where exact figures are confidential, use ranges or rounding, and say that you’ve done so.

According to the ASA’s guidance, the advertising code requires marketers to hold documentary evidence for objective claims before publishing them, and genuine customer testimonials on their own are unlikely to substantiate those claims. A client telling you “revenue went up” isn’t the same as having the figures. This is general guidance, not legal advice, so check the current rules if you’re unsure how they apply to you.

No hard numbers? Qualitative results still count. A decision finally made, a conflict sorted out, or a team that now runs a process without you are all real outcomes.

What formats work for a consulting case study?

Write the full version once and then cut it down for each place you’ll use it. A summary on a service page with a link through to the whole story lets each visitor decide how far to read.

For your website

Give every case study its own page with a clear title, such as “How a 40-person firm fixed its month-end close”. Link it from the relevant service pages on your consultant website, and finish with a call to action.

For proposals

Pick one or two case studies that look like the prospect’s situation and put them near your approach section, where they back up exactly what you’re proposing to do for this particular client. A one-page version with the client’s quote is easier going than a long narrative.

How many case studies do you need?

Two or three good ones make a strong start, ideally spread across your main services or types of client. After that, write one up every time a project wraps, while the details are still fresh. Review them yearly and retire any that no longer reflect your work.

How we can help

We design case study pages and proposal templates as part of our websites for consultants. Where a client is happy to take part, we can also arrange professional photography or a short client video. For the wider picture, see our marketing for consultants. Before any work begins, we agree a clear brief with you, along with the scope and fee.

Sources

• ASA and CAP: Testimonials and endorsements
• ASA and CAP: Substantiation