A testimonial tells customers that someone was satisfied. A case study shows them why. It describes the client's situation, the problem, the approach, the work and the result, giving future customers a detailed picture of what working with you involves. For many service businesses, case studies are the most persuasive marketing material available.
Good case studies are honest, specific and focused on the client's journey rather than on the provider's brilliance.
Choose the right projects
Select projects that represent the work you want more of and the customers you serve best. A strong case study features a recognisable problem, a clear approach and a meaningful result. It does not need to be your largest project; it needs to be relevant to the customers you want to attract.
Follow a clear structure
A simple structure keeps case studies readable:
- The client: who they are and their situation.
- The challenge: the problem they faced and why it mattered.
- The approach: how you worked together and key decisions.
- The result: what changed, with specific details where possible.
- The client's words: a short quotation describing the experience.
This structure mirrors how customers think about their own problems.
Make the client the hero
The client's progress should be the focus. Describe their goals, constraints and achievements. Your role is to guide and support them. Customers reading the case study will imagine themselves in the client's position, so make the story relatable.
Use specific details
Specific details make case studies credible: timeframes, numbers, before-and-after comparisons, photographs, screenshots or examples of deliverables. If exact numbers cannot be shared, describe the result honestly in qualitative terms.
Always obtain the client's permission before publishing identifying details, numbers or images.
Briefly mentioning a challenge and how it was solved can make a case study more believable and show how you handle problems.
Include the difficult parts
Real projects rarely go perfectly. Briefly mentioning a challenge and how it was solved can make a case study more believable and show how you handle problems. Avoid overly polished stories that sound like advertisements.
Keep it concise
Most readers want the essential story, not every detail. A clear headline, a short summary and a few well-organised sections are usually enough. Offer more detail for those who want it, such as images or a longer explanation.
Use case studies throughout your marketing
Place relevant case studies on service pages, in proposals, in sales conversations and in follow-up emails. When a prospect describes a problem, sharing a case study about a similar client can be more persuasive than any explanation.
Common mistakes
Case studies often focus too much on the provider's process and too little on the client's result. Others lack specifics, read like advertisements or are published without the client's permission. Some businesses write one case study and never update it. A small, current library of honest, specific stories works best.
A short interview guide
Case studies are easier to write after a brief conversation with the client. Useful questions include: What was happening before we started? What had you tried already? What made you decide to work with us? What changed, and how do you measure it? What would you tell someone in your position? Record the answers with permission, and use the client's own words where possible.
An example in practice
A small branding studio replaced its gallery of logos with five short case studies. Each explained the client's business, the problem with its previous brand, the design process and what changed after the new identity launched. Prospective clients began referencing specific case studies in their enquiries, and proposals were accepted more quickly because expectations were already clear.