Stop asking customers, just start building with them

What's a Co-Design Test

Co-design is a facilitated workshop where you bring 5-10 target customers together and have them design the product they'd actually buy. Give them cardboard boxes, markers, and craft supplies. Ask them to create packaging that shows features, benefits, and messaging. Then have them pitch it to you like they're selling it at a trade show.

It takes less than an hour. The materials cost almost nothing. And what you learn shapes everything that comes next.

Why this works differently than interviews

Standard customer interviews put you in control. You ask the questions, frame the problems, and interpret the answers. Customers respond to your assumptions rather than expressing their own priorities.

Co-design flips this dynamic. Customers are forced to make trade-off decisions about what goes on the front of the box versus the back. What deserves the headline versus fine print. Which features matter enough to mention versus which get left off entirely.

These forced choices reveal priorities that direct questioning rarely uncovers. When someone designs their ideal product box, they're not just telling you what they want; they're showing you what they'd actually choose when space, attention, and clarity matter.

What a healthcare team discovered in 90 minutes

A healthcare company we work with was building remote patient monitoring tools. After dozens of customer interviews, they felt confident about their value proposition: "comprehensive health tracking with AI-powered insights."

They ran a co-design workshop with 8 hospital administrators and clinical directors. The brief: design the product box for a remote monitoring solution you'd actually purchase.

Three patterns emerged immediately:

First, every group put regulatory compliance and data security front and centre. Not "AI-powered" or "comprehensive", but compliance. This had barely come up in interviews, but when designing something they'd buy, it became the lead message.

Second, the specific features people highlighted weren't the advanced capabilities the team had prioritised. Groups focused on simple integration with existing EMR systems, straightforward alert protocols, and minimal training requirements. The "comprehensiveness" they'd praised in interviews disappeared when designing something practical.

Third, the pitches revealed unexpected use cases. Rather than general monitoring, groups designed solutions for specific scenarios: post-discharge follow-up, chronic condition management, or pre-surgery preparation. The "comprehensive" approach wouldn't work for any of these specific applications.

The team completely restructured their approach based on this single workshop; targeting specific use cases with compliance-first messaging and integration-focused features rather than comprehensive AI capabilities.

What co-design reveals that other methods miss

Actual prioritisation through forced trade-offs

You can't fit everything on a product box. Customers have to choose what matters most, revealing genuine priorities rather than polite interest in all proposed features.

Real messaging in customers' own language

How do customers describe value when they're not responding to your framing? The words they choose for their box designs show you authentic language that resonates.

Hidden constraints and requirements

When customers design something they'd actually buy, practical concerns emerge: procurement processes, implementation barriers, stakeholder approval needs that don't surface in hypothetical discussions.

Feature bundles and relationships

Which capabilities belong together from a customer perspective? Co-design shows you natural groupings that might differ significantly from your technical architecture.

Competitive context and positioning

How do customers differentiate their designed solution from alternatives? This reveals how they think about the competitive landscape and what makes something genuinely distinctive.

How to run effective co-design sessions

Set clear boundaries without over-constraining

Define the problem space ("design a remote monitoring solution") but don't prescribe features or approach. Let customers make actual design choices.

Recruit actual decision-makers or influencers

Co-design works best with people who understand real purchase and implementation constraints, not just conceptual interest.

Use physical materials

Cardboard boxes, markers, stickers, and craft supplies force concrete choices. Digital tools let people hedge and equivocate. Physical constraints drive clearer thinking.

Include the pitch element

Having groups present their designs as sales pitches shows you which benefits they think are most compelling and which features support those benefits.

Take detailed notes on trade-offs

What goes on the front versus back of the box? What makes the headline versus gets mentioned last? These choices reveal priorities better than the final designs themselves.

What you're actually testing

Co-design doesn't validate whether people will buy your solution but it validates which aspects of a solution category resonate most strongly, which benefits matter enough to highlight, and which features support genuine customer needs versus internal assumptions.

Use co-design early when refining value propositions and feature priorities. The outputs inform better experiments; landing pages with resonant messaging, prototypes focused on validated features, positioning that reflects customer language rather than internal jargon.

The evidence strength is relatively low; you're gathering qualitative insights from a small group in an artificial setting. But the insights are often dramatically different from what interviews produce, making co-design valuable for challenging assumptions before heavier validation investment.

Try this next week

Identify a specific aspect of your innovation where you have strong internal opinions but unclear customer validation. Recruit 6-8 target customers for a 90-minute co-design workshop.

Don't ask what they want; have them design what they'd buy, using physical materials that force concrete choices. Watch what they prioritise, listen to how they describe value, and note which trade-offs they make without prompting.

Use these insights to challenge your assumptions before investing in more expensive validation methods.