[15] Wicked problems have features such as no definitive formulation, no true/false solution, and a wide discrepancy between differing perspectives on the situation.
[20] Nigel Cross suggests that "Designers tend to use solution conjectures as the means of developing their understanding of the problem".
[28][29] A five-phase description of the design innovation process is offered by Plattner, Meinel, and Leifer as: (re)defining the problem, needfinding and benchmarking, ideating, building, and testing.
The process may also be thought of as a system of overlapping spaces rather than a sequence of orderly steps: inspiration, ideation, and implementation.
[31] Projects may loop back through inspiration, ideation, and implementation more than once as the team refines its ideas and explores new directions.
[32] Generally, the design innovation process starts with the inspiration phase: observing how things and people work in the real world and noticing problems or opportunities.
These problem formulations 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.
[32] 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.
[33][34] Designers approach user research 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.
[32] The third space of the design thinking innovation process is implementation, when the best ideas generated during ideation are turned into something concrete.
[32] At the core of the implementation process is prototyping: turning ideas into actual products and services that are then tested, evaluated, iterated, and refined.
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.
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.
[10] Lee Vinsel suggested that popular purveyors of design consulting "as a reform for all of higher education" misuse ideas from the fields that they purport to borrow from, and devalue discipline-specific expertise, giving students "'creative confidence' without actual capabilities".
She claimed that promoting simplified versions of design thinking "makes it hard to solve challenges that are characterized by a high degree of uncertainty—like climate change—where doing things the way we always have done them is a sure recipe for disaster".
[82] Stanford University's d.school begins to teach design thinking as a generalisable approach to technical and social innovation.