*3.1. Method: Design Thinking and the Double Diamond Framework*

Design Thinking has always been integral to design practice and the design profession but the approach was introduced to the business community in 2008 [22] and wider community in 2009 [23] by Tim Brown, who defines it as 'a human-centred approach to innovation that draws from the designer's toolkit to integrate the needs of people, the possibilities of technology and the requirements for business success' (see Figure 2); it is also defined as a hands-on, user-centric ideology [24], and a non-linear iterative process that teams use to understand users, challenge assumptions, redefine problems, and create innovative solutions [25], and it has evolved to become an established practice. It has already proved successful to many sectors because it addresses the biases and behaviours that hamper innovation [26]; its value is also recognised well-beyond the design profession, and a number of reputed leadership and training establishments now offer courses in Design Thinking, such as Cambridge University [27] and Massachusetts Institute of Technology, for example [28].

Prior to Brown's public dissemination of Design Thinking, in 2005 the UK Design Council published the Double Diamond, which has become a universally accepted depiction of the design process (see Figure 3). The developers also acknowledged that the process and methods were already integral to, and widely practiced by, the design profession but the diagram was devised to structure the process more clearly and, therefore, to both support designers to progress, from problem to solution, and to help them to explain the process to clients. The original version lists four stages, the first two of which (Discover and Define) encourage broad and deep exploration of the challenge (divergent thinking), while the second two (Develop and Deliver) encourage focused action (convergent thinking) [29].

**Figure 2.** Design Thinking used to initiate innovation, adapted from IDEO.

**Figure 3.** Adapted from Design Council Double Diamond, 2005.

The Double Diamond was also very successful within, and beyond, the design community, and in 2015, it was revised and enhanced to form a framework for innovation and to provide a structure for Design Thinking (see Figure 4). In Design Thinking and the Double Diamond framework, people (stakeholders) are critical to the process and successful project delivery. This is further clarified in the Double Diamond model, which includes stakeholders in all stages as follows. The entire process is underpinned by Engagement (building relationships between citizens, stakeholders, and partners) and Leadership (to create conditions to allow innovation, including culture change skills and mind sets). Design Principles and Methods were also added to the revised Double Diamond model and, again, both specify engagement strategies: Design Principles-1. be people centred; 2. communicate visually and inclusively; 3. collaborate and co-create and 4. iterate, iterate, iterate-and Methods Bank-1. Exploration (of challenges, needs, and opportunities), 2. Shape (prototypes, insights and visions) and 3. Build (ideas, plans, and expertise) [30]. The principles and methods are integrated throughout the process, so stakeholders should be regularly consulted to ensure that the project output meets their current and future requirements.

**Figure 4.** Adapted from Design Council Double Diamond framework for innovation, 2015.
