Design thinking

Design thinking is a term used to represent a set of cognitive, strategic and practical processes by which design concepts (proposals for products, buildings, machines, communications, etc.) are developed. Many of the key concepts and aspects of design thinking have been identified through studies, across different design domains, of design cognition and design activity in both laboratory and natural contexts.
Design thinking is also associated with prescriptions for the innovation of products and services within business and social contexts. Some of these prescriptions have been criticized for oversimplifying the design process and trivializing the role of technical knowledge and skills.
As a process of designing.
Design thinking encompasses processes such as context analysis, problem finding and framing, ideation and solution generating, creative thinking, sketching and drawing, modelling and prototyping, testing and evaluating. Core features of design thinking include the abilities to:
Wicked problems.
Design thinking is especially useful when addressing problems which are "wickedly difficult", in the sense of being ill-defined or tricky, not malicious. Horst Rittel and Melvin Webber contrasted these with "tame" or "well-defined" cases where the problem is clear and the solution available through applying rules or technical knowledge.
Problem framing.
Rather than accept the problem as given, designers explore the given problem and its context and may re-interpret or restructure the given problem in order to reach a particular framing of the problem that suggests a route to a solution.
Solution-focused thinking.
In empirical studies of three-dimensional problem solving, Bryan Lawson found architects employed solution-focused cognitive strategies, distinct from the problem-focused strategies of scientists. Nigel Cross suggests that 'Designers tend to use solution conjectures as the means of developing their understanding of the problem'.
Abductive reasoning.
In the creation of new design proposals, designers have to infer possible solutions from the available problem information, their experience, and the use of non-deductive modes of thinking such as the use of analogies. This has been interpreted as a form of Peirce's abductive reasoning, called innovative abduction.
Co-evolution of problem and solution.
In the process of designing, the designer's attention typically oscillates between their understanding of the problematic context and their ideas for a solution in a process of co-evolution of problem and solution. New solution ideas can lead to a deeper or alternative understanding of the problematic context, which in turn triggers more solution ideas.
Representations and modelling.
Conventionally, designers communicate mostly in visual or object languages to translate abstract requirements into concrete objects. These 'languages' include traditional sketches and drawings but also extend to computer models and physical prototypes. The use of representations and models is closely associated with features of design thinking such as the generation and exploration of tentative solution concepts, the identification of what needs to be known about the developing concept, and the recognition of emergent features and properties within the representations.
As a process for innovation.
A five-phase description of the design innovation process is described by Plattner, Meinel, and Leifer as: "(re)defining the problem, needfinding and benchmarking, ideating, building, testing". Plattner, Meinel, and Leifer state: "While the stages are simple enough, the adaptive expertise required to choose the right inflection points and appropriate next stage is a high order intellectual activity that requires practice and is learnable."
The process may also be thought of as a system of overlapping spaces rather than a sequence of orderly steps: inspiration, ideation, and implementation. Projects may loop back through inspiration, ideation, and implementation more than once as the team refines its ideas and explores new directions.
Inspiration.
Generally, the design innovation process starts with the inspiration phase: understanding the problem or the opportunity. This understanding can be documented in a brief which includes constraints that gives the project team a framework from which to begin, benchmarks by which they can measure progress, and a set of objectives to be realized—such as price point, available technology, and market segment.
Empathy.
In their book "Creative Confidence", Tom and David Kelley note the importance of empathy with clients, users, and customers as a basis for innovative design. Designers approach users with the goal of understanding their wants and needs, what might make their life easier and more enjoyable and how technology can be useful for them. Empathic design transcends physical ergonomics to include understanding the psychological and emotional needs of people—the way they do things, why and how they think and feel about the world, and what is meaningful to them.
Ideation: Divergent and convergent thinking.
Ideation is idea generation. The process is characterized by the alternation of divergent and convergent thinking, typical of design thinking process.
To achieve divergent thinking, it may be important to have a diverse group of people involved in the process. Design teams typically begin with a structured brainstorming process of "thinking outside the box." Convergent thinking, on the other hand, aims for zooming and focusing on the different proposals to select the best choice, which permits continuation of the design thinking process to achieve the final goals.
After collecting and sorting many ideas, a team goes through a process of pattern finding and synthesis in which it has to translate ideas into insights that can lead to solutions or opportunities for change. These might be either visions of new product offerings, or choices among various ways of creating new experiences.
Implementation and prototyping.
The third space of the design thinking innovation process is implementation, when the best ideas generated during ideation are turned into something concrete.
At the core of the implementation process is prototyping: turning ideas into actual products and services that are then tested, evaluated, iterated, and refined. A prototype, or even a rough mock-up helps to gather feedback and improve the idea. Prototypes can speed up the process of innovation because they allow quick identification of strengths and weaknesses of proposed solutions, and can prompt new ideas.
Application.
In business.
Historically, designers tended to be involved only in the later parts of the process of new product development, focusing their attention on the aesthetics and functionality of products. Many businesses and other organisations now realise the utility of embedding design as a productive asset throughout organisational policies and practices, and design thinking has been used to help many different types of business and social organisations to be more constructive and innovative. In the 2000s there was a significant growth of interest in design thinking as a catalyst for gaining competitive advantage within business, but doubts around design thinking as a panacea for success have also been expressed. Designers bring their methods into business either by taking part themselves from the earliest stages of product and service development processes or by training others to use design methods and to build innovative thinking capabilities within organisations.
In education.
All forms of professional design education can be assumed to be developing design thinking in students, even if only implicitly, but design thinking is also now explicitly taught in general as well as professional education, across all sectors of education. Design as a subject was introduced into secondary schools' educational curricula in the UK in the 1970s, gradually replacing and/or developing from some of the traditional art and craft subjects, and increasingly linked with technology studies. This development sparked related research studies in both education and design.
New courses in design thinking have also been introduced at the university level, especially when linked with business and innovation studies. A notable early course of this type was introduced at Stanford University in 2003, the Hasso Plattner Institute of Design, known as the d.school.
In the K-12 education sector, design thinking is used to enhance learning and promote creative thinking, teamwork, and student responsibility for learning. A design-based approach to teaching and learning has also developed more widely throughout education. 
Design thinking can now be seen in International Baccalaureate schools across the world, and in Maker Education organizations.
In computer science.
Design thinking has been central to user-centered design and human-centered design—the dominant methods of designing human-computer interfaces—for over 40 years. Design thinking is also central to recent conceptions of software development in general.
History.
Developing creativity techniques in the 1950s and new design methods in the 1960s led to the idea of design thinking as a particular approach to creatively solving problems. Among the first authors to write about design thinking were John E. Arnold in "Creative Engineering" (1959) and L. Bruce Archer in "Systematic Method for Designers" (1965).
John E. Arnold was one of the first authors to use the term 'design thinking'. In "Creative Engineering" (1959) he distinguishes four areas of design thinking. According to Arnold, design thinking can yield (1) novel functionality, i.e. solutions that satisfy a novel need or solutions that satisfy an old need in an entirely new way, (2) higher performance levels of a solution, (3) lower production costs or (4) increased salability. Thus, according to this early concept, 'design thinking' covers all forms of product innovation, including especially incremental innovation ("higher performance") and radical innovation ("novel functionality"). Arnold recommends a balanced approach: Product developers should seek opportunities in all four areas of design thinking.
Although L. Bruce Archer's "Systematic Method for Designers" (1965) was concerned primarily with a systematic process of designing, it also expressed a need to broaden the scope of conventional design: "Ways have had to be found to incorporate knowledge of ergonomics, cybernetics, marketing and management science into "design thinking"". Archer was also developing the relationship of design thinking with management: "The time is rapidly approaching when design decision making and management decision making techniques will have so much in common that the one will become no more than the extension of the other".
The notion of design as a "way of thinking" in the sciences can be traced to Herbert A. Simon's 1969 book "The Sciences of the Artificial", and in design engineering to Robert McKim's 1973 book "Experiences in Visual Thinking". Bryan Lawson's 1980 book "How Designers Think", primarily addressing design in architecture, began a process of generalising the concept of design thinking. A 1982 article by Nigel Cross, "Designerly Ways of Knowing", established some of the intrinsic qualities and abilities of design thinking that also made it relevant in general education and thus for wider audiences. Peter Rowe's 1987 book "Design Thinking", which described methods and approaches used by architects and urban planners, was a significant early usage of the term in the design research literature. An international series of research symposia in design thinking began at Delft University of Technology in 1991.
Rolf Faste expanded on McKim's work at Stanford University in the 1980s and 1990s, teaching "design thinking as a method of creative action." Design thinking was adapted for business purposes by Faste's Stanford colleague David M. Kelley, who founded the design consultancy IDEO in 1991. Richard Buchanan's 1992 article "Wicked Problems in Design Thinking" expressed a broader view of design thinking as addressing intractable human concerns through design.