Client case studies are one of the most effective selling tools a marketing agency has to grow awareness, build trust, and win business from ideal clients. For agencies in the growth stage, mastering the ability to tell a persuasive story through client experiences is a skill that will continue to pay dividends throughout the life of the business. Here’s why:

  • Case studies are a demonstration, not a statement, of your excellence and if you’re doing your job well, it allows your audience to draw its own conclusions about your value, which is exponentially more effective than one-sided subjective statements like “we’re innovative”, “we have best-in-class tools”, or “our people are our difference”.

  • They showcase your team and their expertise in action, providing valuable context that’s difficult to replicate in a bio.

  • Likewise, they showcase your tools or process in action, providing valuable context that’s difficult to replicate in a process chart or a list of steps. 

  • More than any client list, they provide a deeper understanding of the kinds of businesses you’re qualified to work with and why.

  • They’re adaptable. You can highlight one set of features for one type of client and its needs and others for a different client with different needs.

Their effectiveness, however, depends on how you create them. Here are five best practices to adopt if you want to develop a portfolio of case studies that work hard for you.

1. Start by going to the source

In some cases (no pun intended) you’ll be writing a case study about work done by you and your team together so you’ll have personal knowledge. In other cases, you may be writing about work you had little to do with. This is likely to be true if you’re the dedicated business development person at your agency and have no direct involvement in client deliverables.

This may sound like overly obvious advice, but when it’s time to recreate the magic of your good work, start by talking to the team that did it! You’ll end up with a richer, more effective case study than if you simply asked them to write something up–even if you give them a template, which, no matter how good you think it is, will never replicate a quality conversation.

You want to get deeply familiar with the work that was performed. This includes understanding the business problem the agency set out to solve for the client, the decisions made along the route, the output as a result of those decisions, and of course the end results.

And don’t just talk to your team. Interview them. Encourage them to go beneath the surface facts and recall what made this project or campaign especially challenging or unique. In my own many years of experience writing good case studies, this is where I would find the gems that would have remained hidden if they’d simply filled out a template.

2. Take nothing for granted

Be curious and ask your team to do the same. 

Something else I’ve observed over the years is that what makes a case study interesting is often the stuff the team takes for granted–managing clients and their stakeholders, going the extra mile to secure added value in a media buy, or tapping into deep category expertise, for example. They see this as “just doing their job”. But of course, that’s exactly what your prospective client wants to know–how you do your job better than anyone else.

One useful technique for getting you and your team beyond the surface details is “5 Whys”. The premise is that it takes repeating the question “why” five times before you get to the root cause of a problem. Each answer forms the basis of the next “why” question. 

I will often use this technique with clients not only to help them identify the key parts of a case study that will make it compelling to a prospective client but also to probe for the underlying reason for a decision or the impact of an insight. 

I’m not always appreciated when I’m using the technique. Annoyance is often the first reaction I encounter–annoyance at having to answer what seem like obvious questions. That is, until we arrive at the root cause and then a light goes on, and this beautiful look comes over their faces when they realize that we’ve just now made their case study or pitch idea so much better.

3. Tell a story!

Agencies who know me and have worked with me know that I talk ad nauseam about the important role storytelling plays in new business pitches. The narrative arc of a case study mirrors a classic storytelling arc that leads an audience through each point along the way:

  • Exposition (the client’s situation and business problem)

  • Rising action (the up and downs of research and creative problem-solving)

  • Climax (a campaign launch)

  • Falling action (what happens after the campaign launch)

  • Resolution (the results and lessons learned)

What’s so great about a story is the contrast between the tough challenges faced by the protagonists and how they overcome them. When we know Lassie’s in trouble, we stick around to find out how she’s going to get herself and little Timmy to safety.

Believe it or not, you can create the same effect with your case studies–but you do have to be willing to contrast your victories with your struggles. It makes the story compelling because it’s so relatable. Your audience will instinctively engage with your story–there’s science to back this up.

4. Know the story you want to tell

The good news is that storytelling is a technique we know inherently how to use. After all, humans have been telling stories for millennia to explain the mysterious world we live in and inspire others to action.

But like any tool, it’s more effective if you use it skillfully. 

In terms of creating an excellent case study, this means making good choices around which details to highlight or omit–not because they’re not important; they’re just extraneous to your mission

For instance, if you’re an experiential agency a case study targeted to a CMO might focus solely on the brand-building power of live events. One targeted to the head of events strategy might emphasize your experience managing third-party vendors and events venues. Both are important subplots to the overall story, but each audience cares about different things.

You might also ask yourself what you want your audience to walk away with believing or feeling. 

One of the beautiful things about case studies is their capacity to let the audience draw their own conclusions. A well-crafted one will elicit reactions from your audience like, “that was an innovative idea”, or “they approached that difficult problem with determination and moxie”, or “I’m impressed with how they deployed that new technology”.

5. Get your client involved

The power of your agency’s case studies is turbocharged when you can accompany them with a testimonial statement from the client. That’s because despite the myriad of technology and tools available to you to promote your agency, the number one method marketers consistently rely on for finding a new agency is word-of-mouth and referrals from colleagues and peers

When you can top off a strong case study with a client testimonial, it’s like saying, “don’t take our word for it; hear what your peers have to say about how effective our work is.” 

If you want to be assured of getting your client’s buy-in, it’s important to ask early. Set the expectation that, if you do good work, you will be sharing it with others in the form of a case study. And, if you meet the metrics for success, you’ll be asking the client for a testimonial. In fact, I recommend that you have standard language saying as much that you use in every client contract. 

Another opportunity to plant the seed is at the moment the client is expressing satisfaction with the work you’re doing during the assignment. Thank them, and remind them that, assuming you meet the metrics, you’ll be describing this work in a case study and how much you’d appreciate their participation. 

Of course, you also want to ask at the end of the campaign. They’re already primed, they understand why it’s important and may even be a point of pride that they’re doing their part to support a valued partner.

6. Package it for easy consumption

As I mentioned in the beginning, case studies are adaptable, versatile tools. The same case study can be told in 1200 words (or more) or 120 words (or less). It can be presented from the stage by a live human being or watched as a video. It can be adapted for use in proposals, prospecting emails, awards show admissions, and agency websites.

Just be sure you’re using the right tool for the right job. Depending on the situation, think critically about how you’re packaging your case study. Here are a few things to consider:


What’s the ideal length for a case study? That’s like asking “how long is a piece of string?” It should be as long or as short as the situation requires–and no more.

I recommend creating a written master version of all your case studies. This will encapsulate the whole story, at least as whole as it is at the time of writing (as results come in or as you adapt a campaign for different market conditions, your case history should be updated too). And while there is no hard and fast rule on length, your master version will probably be between 800 and 1500 words.

From this generous piece of content, you will be able to edit down and emphasize the storylines that will mean the most to your audience and position you as a qualified solution for the problem at hand.

This editing process will likely force you to make critical choices about what to keep and what to take out. It’s called “killing your darlings” because it’s hard to cut stuff that you’re proud of. But the objective of a case study isn’t to make you feel good about your accomplishments–it’s meant to win you business so don’t muddy your objective by trying to solve a problem your prospect doesn’t have).


Video case studies sound appealing but they should be used only upon request and that’s most likely to happen in the context of an awards show submission or a competitive agency review. In both those cases, you have a self-interested audience that has consented to view the videos because it will make their job of assessing your work easier.

That’s usually not the case when someone is checking out your work on your website. In most cases, the website visitors are looking to form a quick early impression. The best way to facilitate that is by offering words and images because they’re easier to scan (and you can make it even easier with a good layout). Your audience will appreciate having control over how they consume the content. 

Video on the other hand asks a viewer to invest precious minutes to sit through you presenting the case on your terms, not theirs.

I also don’t love video case studies in a live presentation. I know there are some who believe varying formats helps to keep the audience engaged, but I argue that a live human being connecting with other live human beings–looking into their eyes, watching for reactions, taking questions–is infinitely more effective than cutting to video. 

When you cut to video, you relinquish control over your audience.

(In contrast, a video testimonial is almost always a good idea because we like to see people just like us reassure us that if we buy a product or service it’ll work).


Imagery and work samples are great ways to enhance your case study as long as you provide context and explanation. I see too many cases that use imagery mostly as visual stimulation without context. It’s confusing and may even sabotage a well-written story.

Communicate context through the order in which you display imagery as well as size and layout. 

For instance, a good layout can communicate a sequence of decisions that were made leading to a big idea. If you’re going to show early sketches, explain what they are and how they illustrate your work process. If you’re going to show variations of a campaign execution in different media formats, label them and tell us how they worked together or why you chose one platform over another.

If an image doesn’t actually support the story you’re telling, leave it out. Kill your darlings because more isn’t always better.

Case studies are the workhorses of agency new business because they do a lot of the heavy lifting for you. But, sticking with the analogy for a moment, they deserve to be treated as prized thoroughbreds–treated with utmost care because it’s quite possible they’ll be responsible for winning you millions.

(If you’re wondering where to start in improving your agency’s case studies, download my free guide here.)