Writing guide
How to write a case study
A case study is the asset a salesperson sends when a deal stalls on one question: will this actually work for a company like ours? Its job is to let a prospect watch someone like them succeed, so the claim “this works” arrives in a peer’s voice instead of yours. Nothing else in the content library does that job — a landing page asserts, a demo shows, but only a case study proves with a witness.
Most case studies fail because the vendor writes them about the vendor. The customer becomes a prop, the “challenge” is a sentence of boilerplate, the result is “improved efficiency” with no baseline, and every obstacle has been sanded off in review. What survives reads like an ad with a logo swap — and prospects discount ads to zero. The irony is that the raw material was good; the process destroyed it.
This guide is the working process for keeping the proof intact: choose the customer a prospect will recognize, run a five-question interview that extracts stakes and numbers, keep one piece of friction in the story, and put the result where skimmers will find it — the headline.
What it is
A case study is a documented account of one customer getting a measurable result with your product or method — context, obstacle, approach and outcome, told with real numbers and the customer’s own words. It is a proof asset: marketing publishes it, sales sends it mid-deal.
When to use it
Write a case study when a customer has a result you can quantify and they are willing to stand behind it — typically to arm prospects in evaluation who are asking whether this works for companies like theirs. Skip the format when the result is vague goodwill (“the team loves it”), when the customer will not approve numbers or a name, or when the story is really one strong quote — a testimonial does not need 800 words of scaffolding around it.
The structure that works
A result-first headline
Prospects skim a case-study library the way they skim search results. The number is what stops the scroll; a headline that hides it loses the reader the story was built for.
- Use the formula customer + metric + timeframe: “How Harlan Freight cut quote turnaround 62% in one quarter”.
- Lead with the metric your buyers evaluate on, not the one that flatters most.
- Delete “Customer Success Story:” prefixes — they label the document instead of selling it.
A context snapshot the prospect can match
The first question every reader asks is “are they like us?”. Until size, industry and situation click into place, the results belong to someone else.
- Give the matching details in 2 to 4 sentences: headcount, industry, stack, the constraint that defines them.
- Include the oddly specific detail that makes it real — a team of 9, 40,000 SKUs, three warehouses.
- Add a three-stat sidebar box; it is what gets lifted into sales decks.
The challenge, with its cost
Stakes make results meaningful. A problem that cost nothing to leave unsolved makes any solution worth nothing.
- Quantify the before state — hours lost per week, error rate, revenue slipping to slower quotes.
- Name what they tried first and why it fell short; failed alternatives are context, not embarrassment.
- Let the customer describe the low point in a direct quote.
The approach, including the friction
This is where credibility is won or lost. A frictionless rollout reads as fiction, because every buyer has lived through a real one.
- Walk the implementation in steps with durations: who did what, in which week.
- Keep one thing that went wrong or took longer than planned, and how it was resolved.
- Prefer specifics to abstractions — “the ops lead spent two afternoons mapping fields” beats “seamless integration”.
Results with verifiable numbers
The section prospects screenshot and forward — and the section procurement will challenge. Build it to survive both.
- Report baseline, after, and timeframe — never a lone percentage.
- Say how each number was measured and whose dashboard it came from.
- Translate each number into operational meaning: “43 hours a month — one working week back”.
Lessons and one next step
The close belongs to the customer’s voice, followed by a single path forward for the reader who just watched a peer succeed.
- End on the peer-recommendation quote from the interview, not on a product paragraph.
- Offer exactly one CTA matched to evaluation stage — a demo, a related case study — not a menu.
- Cut any closing section that re-explains what your product does; the story already did.
Step by step
- 01
Pick the customer a prospect will recognize
Selection beats writing: the best-told story about the wrong customer moves no deals. Filter candidates through three questions — is the result measurable (a number, not a mood), is the customer in a segment you are actively selling into, and will a named human stand behind it? A mid-market customer with a 38% improvement in your target vertical outsells a famous logo with an unquotable one.
Timing controls the yes. Ask at the peak — the week they report the win in a review call, renew early, or thank your team unprompted. The same request six months later lands as a favor; at the peak it lands as recognition. Aim to leave every strong quarterly review with case-study permission on the table.
- 02
Run the five-question interview
Book 30 minutes, record it, and ask five questions in this order: What was going on that sent you looking for a solution? What else did you try, and why didn’t it stick? What nearly stopped you from choosing us? What can you measure now that’s different? And what would you tell someone in your seat who’s considering this?
Each question has a job. The first two produce the stakes and the failed alternatives. The third hands you the exact objection your prospects share — already resolved. The fourth produces the headline. The fifth writes your closing quote in peer language no copywriter can fake. When an answer comes back vague, ask “what did that look like in numbers?” and then stay silent; the pause does the interviewing.
- 03
Pin the numbers down before drafting
For every result, capture four facts before you write: the baseline, the after, the timeframe, and how it was measured. “Support tickets down 38%, from 214 to 133 a month, across the 90 days after rollout, per their helpdesk export” survives procurement scrutiny; “dramatically fewer tickets” does not survive a raised eyebrow.
When a number is commercially sensitive, negotiate the form rather than surrendering the substance: a percentage without absolutes, a range, a multiple (“4x faster”). Anonymizing the company is the last resort — and if you must, compensate with precision everywhere else (industry, headcount, region, use case), because “a leading company” is a phrase readers have learned to read as fiction.
- 04
Write the headline as the result
The formula is customer + metric + timeframe: “How Harlan Freight cut quote turnaround 62% in one quarter”. Write 5 to 10 variants and keep the one whose number your prospect’s boss would stop on. Put the customer’s name first when you have naming rights — a recognizable peer is half the click.
Choose the metric your buyers already evaluate on, even when a different one is bigger. If buyers care about time to first value, a 62% onboarding cut beats a larger but irrelevant number. Keep the units honest, too: “62% faster” and “62 percentage points” are different claims, and the readers you most need to convince know the difference.
- 05
Draft the story with the customer as protagonist
The customer acts in every scene — they diagnosed, they rolled out, they measured — and the product assists. Use their recorded words for the stakes, the turning point and the verdict. Clean up grammar, but never polish a quote into marketing language the speaker would not say aloud; the roughness is the fingerprint that proves a person said it.
Keep the friction that question three surfaced: the objection they almost walked on, the two weeks of messy data cleanup, the feature that confused everyone at first. One honest snag per story is the target. Prospects have read a hundred frictionless case studies; the snag is the part that reads as true — and it pre-handles the same objection forming in their own head.
- 06
Cut the vendor-speak in the edit
Count product mentions: in an 800-word case study, more than five or six means the brochure is winning. Replace product adjectives — “powerful”, “seamless”, “robust” — with nothing at all; the numbers already carry the judgment. If a sentence could move to your homepage unchanged, it is advertising, and it dilutes the story that was doing the persuading.
Apply the same razor to the customer: “innovative industry leader” is flattery, not context. The reader needs matching details — size, stack, constraint — not compliments. A case study documents; the moment it praises, its evidence starts discounting.
- 07
Get sign-off, then package it three ways
Send the customer the full draft with every number and quote highlighted, and agree in writing what is public, what is sales-conversation-only, and what is off limits. At enterprise customers, budget 1 to 2 weeks for comms or legal review — and defend the numbers in that negotiation, because a case study that loses its numbers has lost its reason to exist.
Then cut the approved master into three formats: the web page with a three-stat summary box near the top, a one-page PDF under 400 words for sales follow-ups, and a single slide carrying the headline number and one quote. The slide will appear in more deals than the page will ever be read — build it yourself rather than leaving it to each rep.
Before and after: what good looks like
Before
Acme Logistics is a leading provider of freight solutions with a strong commitment to innovation. Like many companies in the industry, Acme was facing challenges with manual processes that impacted efficiency. After evaluating several options, they selected our platform for its powerful automation capabilities. The implementation went smoothly, and the results have been impressive. Acme has seen significant improvements in productivity and team satisfaction, and continues to expand its use of the platform across the organization.
After
Acme Logistics was quoting freight jobs by hand — 40 minutes each, 60 quotes a week across a team of five. Quoting was the bottleneck that kept them off larger contracts. Two months after moving quoting onto the platform, the average quote takes 9 minutes and the team handles 140 a week without new hires. “I assumed we’d trade accuracy for speed,” says ops director Lena Ortiz, whose team initially pushed back on automated rate tables. “Error rate went the other way — from about 4% of quotes to under 1%.” The full rollout, including two weeks of rate-card cleanup nobody had budgeted for, took 60 days.
The before is written by the vendor, for the vendor: “leading provider”, “powerful capabilities”, “impressive results” — 76 words with no number, no name and no friction. The after tells the same story with a baseline (40 minutes, 60 quotes), an after state (9 minutes, 140 a week), a named human, and two details an ad would delete: the team’s initial pushback and the unbudgeted rate-card cleanup. Those two admissions are what make the 4%-to-1% claim believable.
Mistakes that sink a case study
| Mistake | The fix |
|---|---|
| The vendor is the hero of the story | The customer acts; the product assists. If a paragraph could survive on your homepage unchanged, it does not belong in a case study. |
| Results with no baseline — “improved efficiency by 40%” | Report before, after, timeframe and how it was measured. A percentage without a denominator is a claim, not a result. |
| Sanding off every obstacle in review | Keep one snag and its resolution. Frictionless stories read as fiction, and the near-objection from the interview is your most persuasive paragraph. |
| Burying the result in the final section | Put it in the headline and again in the first 100 words. Prospects skim a case-study library; the number is why they stop. |
| Anonymous everything — “a leading SaaS company” | Trade for naming rights: co-marketing exposure, a backlink, roadmap input. If the name truly cannot be used, compensate with precise context — industry, headcount, region, use case. |
| Writing it once and shipping it one way | Cut the approved master into a web page, a one-page PDF and a deck slide. The slide gets shown in more deals than the page gets read. |
Pre-publish checklist
- The headline contains a metric and a timeframe, not the words “success story”.
- The main result appears within the first 100 words.
- A context snapshot (size, industry, use case) lets a prospect answer “are they like us?” in ten seconds.
- The before state is quantified — what the problem cost in hours, money or errors.
- Every result reports baseline, after, timeframe and measurement source.
- At least two direct customer quotes appear, including one about a doubt or obstacle.
- One thing that went wrong or ran long stays in the story, with its resolution.
- Product adjectives (“seamless”, “powerful”) are gone; numbers carry the judgment.
- The customer approved the final text, numbers and quotes in writing.
- The close is the customer’s peer-recommendation quote plus exactly one CTA.
- A three-stat summary box exists for skimmers and for the sales deck.
Free tools for this work
Check your case study before it ships.
Frequently asked questions
- How long should a case study be?
- 600 to 1,000 words for the web version — a prospect gives it two to three minutes. Past 1,200 words the vendor is usually narrating; cut back to the numbers, the quotes and the turning points. The sales one-pager should stay under 400 words, and the deck version is one slide: headline number plus one quote.
- How do I get a customer to agree to a case study?
- Ask within a week of them reporting the win — agreement rates fall as the result ages. Make the ask small and concrete: one 30-minute recorded call and one approval pass. Offer a trade when needed: co-marketing exposure, a backlink, roadmap input, or renewal goodwill. For enterprise deals, add case-study participation as an optional clause at contract time.
- What if the customer won’t share exact numbers?
- Negotiate the form, not the existence: a percentage without absolutes (“38% fewer tickets”), a range (“from roughly 200 to under 140”), or a multiple (“4x faster”). Most refusals are about revealing scale, not improvement — hide the denominator and keep the delta. Full anonymization is the last resort and costs most of the asset’s power.
- How many case studies do I need?
- One per segment you sell into beats ten from the same segment. Start with three: your core vertical, your fastest-growing vertical, and the deal size you most want to repeat. A sales team actively uses 3 to 5; beyond that, reps stop knowing the library and default to the newest one anyway.
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