The Double Diamond method

The Double Diamond framework stands as one of the most powerful and versatile approaches to product development and problem-solving. Created by the British Design Council in 2005, this framework provides a structured yet flexible process for tackling complex challenges while keeping human needs at the centre of all decisions.

Understanding the Double Diamond

The Double Diamond visualizes the design process as two adjacent diamonds, each representing a distinct phase of thinking: problem exploration and solution development. Each diamond contains two modes of thinking - divergent (expanding possibilities) and convergent (narrowing focus). This creates four distinct phases:

1. Discover (First divergent thinking phase)
2. Define (First convergent thinking phase)
3. Develop (Second divergent thinking phase)
4. Deliver (Second convergent thinking phase)

The brilliance of the Double Diamond is that it reminds us to apply both divergent and convergent thinking not just to solutions (the second diamond) but also to understanding problems (the first diamond). This helps teams avoid the common pitfall of rushing to solve problems before fully understanding them.

The First Diamond: Understanding the Problem

Discover Phase: Exploring the Problem Space

The Discover phase is about opening up and gathering broad insights about the problem space. Teams cast a wide net to collect diverse information without judgment or filtering.

Key activities in this phase include:

• User interviews and observation
• Market research
• Trend analysis

Case Study: Airbnb's Discovery Process

When Airbnb was struggling with low bookings despite decent website traffic, they entered a discovery phase rather than immediately redesigning their platform. Their team travelled to meet hosts, conducted extensive interviews, and personally experienced the service as guests. This immersive research revealed something crucial: while their website worked functionally, the low-quality photos of listings failed to build trust and desire. This insight came not from website analytics but from direct observation in users' environments.

The discovery revealed their real problem wasn't website conversion optimisation but rather establishing trust through better visual representation of listings. By spending time in this divergent thinking phase, they identified a problem they hadn't originally considered.

Define Phase: Narrowing and Focusing

The Define phase involves synthesising discovery insights into a clear, actionable problem statement. It's about converging on the specific challenge worth solving.

Key activities include:

• Problem statement creation
• "How Might We" question formulation
• User persona development
• Journey mapping

Case Study: Spotify's Define Phase

Spotify's discovery research showed that while users enjoyed their personal music libraries, they struggled with the effort of finding new music they'd love. In their define phase, they synthesised research findings into a specific problem statement: "How might we help users discover new music they'll enjoy without creating additional work?"

This focused problem statement led to the development of their Discover Weekly feature. By synthesising listening data across users with similar tastes, they created personalised playlists requiring zero effort from users. The success of this feature came from properly defining the problem as one of effortless discovery rather than simply offering more music choices.

The Second Diamond: Creating the Solution

Develop Phase: Exploring Possible Solutions

The Develop phase opens up thinking again to generate multiple solution ideas that address the defined problem. This divergent thinking encourages creativity and innovation.

Key activities include:

• Ideation workshops and brainstorming
• Concept sketching
• Rapid prototyping
• Co-creation sessions with users
• Solution prioritisation
• Technical feasibility assessment

Case Study: IDEO's Shopping Cart Redesign

When IDEO tackled the challenge of reimagining the shopping cart, they used the develop phase to generate numerous possible solutions. Rather than jumping to a single design concept, they created different prototypes addressing various aspects of the shopping experience: manoeuvrability, child safety, checkout efficiency, and organisation.

Their teams built multiple rough prototypes from materials like PVC pipe and wheels from roller skates. This divergent approach to solution development allowed them to explore various directions simultaneously and combine the best elements from different concepts. The result was a revolutionary cart design that better met shopper needs while remaining feasible for mass production.

Deliver Phase: Refining and Implementing

The Deliver phase converges again to refine the most promising solutions into a final, implementable form. This involves testing, iterating, and preparing for launch.

Key activities include:

• Solution refinement
• User testing and feedback incorporation
• Technical development
• Implementation planning
• Launch preparation
• Measurement framework creation

Case Study: Square's Payment Solution

Square's deliver phase for their original credit card reader shows how convergent thinking refines solutions to their essential elements. After exploring various payment concepts, Square focused on creating the simplest possible card reader that could work with existing smartphones.

Through multiple iterations of user testing with small merchants, they refined the design to address specific pain points: quick setup, reliability, size, and cost. Each iteration removed unnecessary complexity until they arrived at their iconic small square reader that plugged directly into a smartphone's audio jack. This rigorous refinement process delivered a solution perfectly aligned with their defined problem: making credit card acceptance simple and accessible for small businesses.

Common Pitfalls and How to Avoid Them

Rushing Through Discovery

Pitfall: Teams often rush discovery, believing they already understand the problem.

Solution: Set a minimum time commitment for discovery (e.g., two weeks) regardless of how well the team thinks they understand the problem. Require a minimum number of user interactions before proceeding.

Case Example: Dropbox initially planned to launch with a feature-rich product but committed to extensive discovery first. This research revealed users valued simplicity and reliability over numerous features, fundamentally changing their product direction and contributing to their success.

Solutions Looking for Problems

Pitfall: Teams sometimes start with a solution in mind and work backward.

Solution: Begin projects by articulating the problem to solve, not the solution to build. Have stakeholders frame requests as problems ("Users struggle to find relevant content") rather than solutions ("We need a new search algorithm").

Case Example: Nintendo's Wii emerged from defining the problem as "How might we make gaming more accessible to non-gamers?" rather than the solution-first approach of "How do we build a more powerful console?" This problem-first approach led to revolutionary motion controls rather than competing on processing power.

Skipping Iteration in the Deliver Phase

Pitfall: Teams often treat the deliver phase as simple execution rather than continuous refinement.

Solution: Build multiple testing cycles into the deliver phase. Set expectations that the first implementation will be refined based on real-world feedback.

Case Example: Gmail remained in beta for five years, allowing continuous refinement based on user feedback before "final" launch. This approach enabled them to develop features like conversation threading and spam filtering that perfectly addressed user needs.

Integrating Double Diamond with Agile Methodologies

Many organizations struggle to reconcile design thinking approaches like the Double Diamond with Agile development methodologies. Here's how to integrate them effectively:

Dual Track Agile

Implement a dual-track approach where discovery and definition work runs ahead of development sprints:

• Discovery Track: Research and problem definition work
• Delivery Track: Development sprints implementing solutions

This allows discovery to inform upcoming development sprints while keeping both processes moving forward.

Sprint Zero

Dedicate initial sprints (often called "Sprint Zero") to discovery and definition before beginning solution development. This ensures the team starts with a clear understanding before building.

Design Sprints

Incorporate Google's Design Sprint methodology as a way to quickly move through a miniature Double Diamond process for specific features or challenges within the larger product development effort.

Conclusion

The Double Diamond framework transforms product development from a solution-focused process to a human-centered journey of discovery and creation.

By giving equal importance to understanding problems and creating solutions, teams develop products that truly meet user needs rather than simply implementing preconceived ideas.

The most successful organisations don't view the Double Diamond as a rigid methodology but as a mindset—a commitment to exploration before execution, to understanding before building. When properly implemented through structured workshops, clear phase gates, and appropriate tools, this framework leads to solutions that resonate deeply with users while achieving business objectives.

Remember that the Double Diamond isn't about following steps mechanically—it's about embracing both creative exploration and focused execution at the right moments. By honouring each phase of the process, you build not just better products but a deeper understanding of the people you serve.