The Double Diamond

The Double Diamond is the basis of the design methodology which we are using in the Bexley Innovation Lab. Different designers will use different methods and models, but they all share similar characteristics. The models maps how the design process moves between thinking as broadly as possible and narrowing down to specifics.

There are four phases in the Double Diamond (so-called because of this pattern of broadening out and narrowing down). Generally a design project will move through every one of these stages, although not necessarily in this order and perhaps visiting some stages more than once.

Double Diamond


Each design project begins with a discovery phase. This phase is about gathering insights and initial ideas, and understanding the system or service that you want to innovate within.

As well as looking at data and other desktop research, much of the Discover phase is spent on user research – speaking to people and observing real-life situations to get a feel for how the people using a service experience it and what it is they’re trying to do.

In this phase, designers are looking to learn as much as they can, gathering insights and inspiration from as many people and situations as possible rather than focusing in too early on a specific design path. At the end of this phase, as well as a better understanding of the experience of users, designers will have identified lots of opportunities for innovating and designing something new.



Define is all about making sense of the everything we’ve learnt during Discover and deciding which of the possibilities for design we’d like to pursue. Having identified many options, its unlikely we’ll be able to design for them all within the scope of one project. At this stage we have to make decisions about what problem we’re trying to solve and what issue we think is the most important to tackle now.

This phase narrows down rather than broadening out because we need to get into specifics before we can start designing. At the end of this phase, the design team will have a problem definition statement, that’s been agreed and signed off with the project team, which gives a really clear direction for the next phase.




The Design phase is another phase of broadening out, as designers come up with solutions for the problem they have defined. This will include brainstorming to generate as many potential solutions as possible, taking inspiration from the research done with users during discovery.

A key part of the design phase is multi-disciplinary working. To design a service that is useful to people, everyone who uses it, from customers to administrators, needs to be involved, through activities like co-design workshops. Including people with different skill sets and backgrounds in these workshops and in the project team means that there’s a broader base to draw potential solutions from.

At the end of this phase, designers will have developed user personas to specify who they should be keeping in mind while they’re designing the service, as well as concepts for how the service might look.



Please test.JPG

The Deliver phase once again closes the process down into specifics – this time into a final service or product to be implemented. This is done through prototyping, testing and iterating. By building a basic (and cheap) version of a product or service which users can get their hands on and test in real life, designers can find out more easily what works and what needs to change, and then go back to users having made these changes. This means that the final product is something which works for the people it has been designed for, rather than a ‘big reveal’ which may not.

At the end of the end of this phase, designers would have prototypes, business cases and delivery plans so that they can move into implementing their solution.


If you’d like to find out more about the Double Diamond take a look at this guide from the Design Council. Or you can find out about other design methodologies from IDEO and Stanford D-School.