25 October 2013

Review: Design Thinking

The following was submitted to the University of Pennsylvania's School of Design as part of the Systems Thinking elective in Fall 2013.

Design Thinking: Understanding How Designers Think and Work (2011) provides an introduction to the field of design thinking, the “core creative process for any designer”. (1) The author, Nigel Cross, has chosen to structure the book around a series of in-depth case studies, across a range of design disciplines, including architecture, product design and sports engineering. By drawing upon an extensive range of existing empirical studies, comparing and contrasting them, Cross is able to draw out patterns and common themes that provide the basis for design thinking practices.

Design Thinking: Understanding How Designers Think and Work
(Bloomsbury Academic, 2011)

Nigel Cross is Emeritus Professor of Design Studies at the Open University, UK, where he teaches courses in design and technology at undergraduate level. With a background in architecture and industrial design, he has been engaged in design research, with a focus on design methodology and design epistemology, since the nineteen-sixties. His primary interest is in “design cognition, analysing the cognitive activities and abilities of designers, through protocol and other studies.” (2) Design Thinking is the latest publication from Cross and follows on from Designerly Ways of Knowing (Springer, 2006) and Engineering Design Methods: Strategies for Product Design (Wiley, 2008). In 1991 he initiated, alongside Norbert Roozenburg and Kees Dorst of Delft University of Technology, the Design Thinking Research Symposia.

It is this authoritative background that Cross brings to bear on the subject of design thinking and whilst by Cross’s own admission the book cannot be said to extend the field theoretically, (3) it largely succeeds in its aim of “revealing what designers do during the activity of designing, and on building an understanding of the nature of design ability.” (4)

Structure and Approach

The book is divided into eight chapters, with half of those chapters focused solely on in-depth case studies and the remainder concerned with making sense of the observations made in those studies. A pattern quickly emerges wherein Cross outlines two case studies, before comparing and contrasting them in the proceeding chapter, and then repeats this process. Whether knowingly or not Cross has provided a manifestation of the iterative design processes he sets out in Chapters 1 and 8 within the very structure of his book, taking a set of concepts, testing them, refining them and building upon them to provide clarity to the situation. (5) Early on Cross outlines the three main methods of researching the act of ‘design’: empirical studies; reflection; and theorising.­­ Whilst not rejecting the second and third approaches, Design Thinking relies heavily on the various different methods of empirical studies to establish it’s arguments so that the author can “build an evidence-based understanding of how designers think and work.” (6) Of the four general categories of empirical studies—interviews, (7) observations and case studies, (8) experimental studies, simulation—Chapters 2 and 3 are interview-based and Chapters 5 and 6 experiment-based. Although Cross makes use of numerous other sources to develop his arguments where possible he attempts to remain within the boundaries of the extensive case studies presented in Chapters 2, 3, 5 and 6, only over stepping these boundaries and making use of other examples where absolutely necessary.

Following a brief, separate introduction, Chapter 1 itself is very much a general introduction to the topic of design thinking, introducing all of the main themes and concepts that will be discussed throughout the later chapters, including the wealth of other authors Cross will be drawing upon in order to reinforce his own observations. This general, all-encompassing approach, can leave the reader feeling a little over whelmed, with the number of themes discussed contributing to this being the longest chapter, however this is a necessary step as it enables Cross to distil these themes into a narrow, more concentrated band. (9)

The interview-based case studies follow, with Chapter 2 discussing the accomplishments of Gordon Murray, a highly successful Formula One racing car designer, and Chapter 3 focused on Kenneth Grange, a product designer who has worked on everything from the design of sewing machines to high speed trains. Drawing upon the similarities of both Murrary and Grange design processes, Cross outlines ‘How Designers Think’ in Chapter 4, adding detail to the concepts first introduced in Chapter 1 and defining a series of lists that includes three strategic aspects of design thinking: “taking a broad ‘systems’ approach to the problem … 'framing' the problem in a distinctive and sometimes rather personal way … [and] designing from first principles.” (10) A possible fourth aspect, conflict, is also alluded to. Furthermore, Cross sets out the shared features of successful, innovative design (11) with a distinction between personality characteristics and methods and approaches, the implication being that while the latter can be taught, the first set cannot. (12)

In Chapters 5 and 6, the experiment-based base studies, a design project is tackled by an individual ‘expert’ designer and a three person team of experienced designers; each is conducted in a recorded, laboratory situation with the individual designer encouraged to vocalise his thoughts throughout. (13) These exercises are an example of protocol analysis—an empirical, observational research method for analysing design activity—which is “regarded as the most likely method to bring out into the open, at least to some extent, the mysterious skills of design thinking.” (14) Chapter 7, ‘How Designers Work’, compares the findings of the two experiments; the idea of ‘scheduling’ a design process is key to the discussion. Cross demonstrates that a similar design process is followed in both cases; first the task is clarified, second they search for concepts and third the concept is fixed. Thus design is portrayed as “an ongoing interactive exploration of both the problem and solution” which is described by Dorst and Cross as “the ‘co-evolution’ of problem and solution” or “a strategy of incremental development” by Goel. (15)

Cross sets out the argument for a seventh form of intelligence, design intelligence in the eighth and final chapter, ‘Design Expertise’. Six ‘traditional’ forms of intelligence are described—linguistic, logical-mathematical, spatial, musical, bodily-kinaesthetic, and personal—however Cross is of the opinion that “Aspects of design ability seem to be spread through these various forms of intelligence in a way that does not always seem entirely satisfactory.” (16)  The only “reasonable” solution for him is to separate design intelligence out as a seventh separate intelligence, defined as one that “involves an intense, reflective interaction with representations of problems and solutions, and an ability to shift easily and rapidly between concrete representations and abstract thought, between doing and thinking.” (17) A short final case study is used as a demonstration of the high-level cognitive functions that determine design thinking, with a simple design problem presented to a healthy control subject and a patient who has suffered neurological damage. Whilst the patient can recognise that this is a simple exercise, based on his extensive personal experience as a designer, he is unable to complete the exercise. Cross though is keen to stress that “like other forms of intelligence and ability, design intelligence is not simply a given ‘talent’ or ‘gift’, but can be trained and developed.” (18)

The book ends with a slightly disappointing discussion on how these skills can be developed, with comparisons drawn between the ‘depth-first’ design approach of the novice (the student) compared to the ‘breadth-first’ design approach favoured by the expert; the topic seems slightly rushed within the wider context of the book and would have justified a separate chapter. (19) However, it is important to note that Cross never sets out to provide a ‘how-to’ book. The more likely  reason for this discussion being is that it provides a demonstration of how it is only with time that designers can accumulate experience and add to their personal ‘design domains’ which are key to formulating solution-concepts.

The focus of this paper will now shift slightly from a broad over view of Design Thinking to further analysis of the key themes that run throughout the book.


Early on in Chapter 1 Cross introduces the idea that design cannot be conducted as a purely internal mental process, rather “the designer needs to interact with an external representation … [and] engage with the exploration of both the problem and its solution.” (20) The concept of ‘designing’ was originally not separate from the activity of ‘making’ and this is still evident in traditional, craft-based societies today. (21) Although Cross does not go into the context behind this separation, the introduction of a prior activity of drawing or modelling an artefact subtly shifts the focus so that in many cases the mere act of designing can become an end in itself, as witnessed by the practice of ‘paper architecture’. However, there is a clear distinction between the act of representing something that will be realised as an artefact and the representation being the artefact in its own right.

Drawing, alongside examining and thinking, is one of three design activities identified by Cross in Chapter 7. The activity of ‘drawing’ is not in itself key to the argument, Cross is using it as a simplification, a means to describe any activity that enables the designer to make a physical representation of the real world. This is demonstrating most vividly in Chapter 2 where Gordon Murray uses sketches to portray his thinking, an iterative process of sketching one concept, focusing on the successful component and redrawing it and then repeating this process until 90% of his prior sketches are redundant. All designers it seems use representations as “a means of ‘thinking aloud’, or ‘talking to themselves’, as Gordon [Murray] put it.” (22)


A recurrent theme in the observations made about the case studies is the importance of “’uncertainty’ and is best summarised by Ted Happold who is attributed with saying that “Coping with uncertainty … seems to be a key factor in design ability.” (23) As the ideas in the book develops the notion of risk taking is also brought into the discussion as “the difference between the innovative and non-innovative designer.” (24) It is the uncertainty of the outcome that creates the risk. Designers must come to “tolerate and work with uncertainty” and it is perhaps for this reason that they are more willing to take risks. (25) By embracing uncertainty and risk a designer is also opening him- or herself up to the possibility of failure: “The innovative designer is prepared to fail (occasionally), but is not afraid of failure, and of course seeks fanatically to avoid failure.” (26)


The importance of collaboration in design is demonstrated most clearly by Cross through the experiment-based case study in Chapter 6. Cross states in the Introduction that he is interested in taking an interdisciplinary approach to design it is therefore unsurprising that he devotes a large portion of Design Thinking to the concept of teamwork. (27) Nevertheless numerous studies have shown that design is in fact a collaborative act, as Cross demonstrates when quoting Dianne Murray “Design is not hidden, it is constructed in public so other people can read it, and accepting commentary on it from anybody else is part of a tradition they embody.” (28) For Larry Bucciarelli “the process of designing is a process of achieving consensus among participants with different ‘interests’ in the design” furthermore “the social nature of designing, he suggested, results in acknowledging the inevitability of uncertainty and ambiguity” (29)
The case studies, primarily, would seem to support these propositions and it could be argued that a team can consider more problems at once than a lone designer, dealing with increased complexity.  Key to a successful team is how they are able to ‘negotiate difference’, that is how do they cope with there is a conflict between different views in the team. This negotiation allows teams to “accumulate the discourse” and “to make a constructive contribution that focuses the previous discussion onto a type of solution concept that suggests a way forward.” (30)

Care must be taken however to ensure that information is shared properly between all members of the team so that a common shared understanding can be developed. The more coherent a team is, avoiding non-committal apparent agreements, the more successful that team is likely to be. (31)

A personal exercise

Despite the emphasis on team working and collaboration, design remains a deeply personal exercise, with a team members ability to draw upon personal experiences of utmost importance. It is of course also “quite normal for designers to become emotionally involved with their ideas; their design concepts are not merely abstract ideas, but personal insights that emerge as a result of some considerable cognitive effort.” (32) Successful or innovative designers also share common characteristics, including a very high personal motivation and are “steeped in the knowledge and expertise of their domains.” (33) This knowledge can only be developed over time, allowing designers to eventually develop “schemata”, based on the precedents they are able to draw upon, which enables them to draw patterns between data sets more quickly. (34)

Insight follows immersion

Comparative studies into the different working methods of designers have revealed a common thread: insight follows immersion. This immersion typically takes the form of quickly switching between the three types of design activities, for an extended, concentrated period. It would seem that design ‘inspiration’ (if there is such a thing) comes when the mind is preoccupied, allowing the sub-conscious to think through a problem and ‘join up the dots’. This ‘insight’ will often occur when a designer then steps away from the problem, during a period of relaxation, so that “the solution details then cascade from the concept.” (35)

Solution-focused, not problem-focused

For much of the book the focus seems to be that designers are problem-focused, and it could perhaps come as a surprise when Cross, in Chapter 8, states that “designers are solution-focused, not problem focused.” (36) The explanation behind this statement is that designers do not take an initial problem, rather they reframe the boundaries of the initial problem, pushing it to the limits where before there was a safe buffer zone between the ‘accepted solution’ and the rules which defined it. (37) For this to happen both problem and solution must ‘co-evolve’ and go back to ‘first-principles’. In so doing designers construct their own solutions: “In a sense they are genuine explorers.” (38)

Everyone can design

The final concept that is central to Cross’s discussion on Design Thinking is one he makes at the very start of Chapter 1, that “Everyone can – and does – design.” (39) What this statement seeks to do is open up the realm of ‘design’ to everyone. Cross goes on to add that “Although everyone can design, designing is one of the highest forms of human intelligence.” (40) The level of cognitive skill, demonstrated clearly in Chapter 8, is based on synthesis or abduction, as opposed to the two conventionally understood forms of reasoning: deduction and induction. (41) As designers learn through the six phases of development, described by Hubert Dreyfus, they develop a “boader and more complex understanding of what has to be achieved.” (42) Whilst everyone can design, it is only through repetition of ‘design’ as a creative act that design thinking can be improved; “Like learning a language, it is a matter of immersion and internalising different levels of understanding and achievement.” (43)

Formulating design in a construction context

In summary it seems that designers should pay closer attention to the processes by which they design and the way in which they Think about design. In architecture this is often achieved through design process maps, flowcharts or diagrams, including the RIBA Plan of Work. What all of these attempt to do is ‘flatten’ the Design Thinking described by Cross--essentially an iterative process although he does not call it such.

Process maps, including the RIBA Plan of Work 2013, 'flatten'
the iterative design process into a number of stages and activities.

The difficulty of course lies in planning for the “unplanned, ad hoc exploratory activities to be pursued when they are perceived as relevant by the designer.” (44) A designers skill must also lie in knowing how to both make use of “opportunistic behaviour” and step forward to progress their design solutions.


The following was submitted to the University of Pennsylvania's School of Design as part of the Systems Thinking elective in Fall 2013.

1. Cross, N., Design Thinking (2011), Blurb
2. Nigel Cross Profile, The Open University,, 17th December 2012 [Accessed: 11th September 2013]
3. Book Comment: Nigel Cross Design Thinking,, 20th May 2011 [Accessed: 11th September 2013]
4. Cross, op. cit., (2011), p. 1
5. The author of this paper believes this is a deliberate, conscious act by Cross.
6. Cross, op. cit., p. 134
7. For examples of interviews with architects see Hans Ulrich Obrist’s ‘Conversation Series’.
8. For observations and case studies see Albena Yaneva’s research “An Ethnography of Architecture, including her book “Made by the Office for Metropolitan Architecture: an Ethnography of Design”. Presents the everyday practice of architects OMA as an enquiry into architecture-in-the-making, based on participant observation, extensive interviews and photo-documentation of various projects, such as: the Seattle Public Library; the Whitney Museum of Modern Art, New York; China Central Television (CCTV) and La Casa da Musica, Porto.
9. This is not too dissimilar to Gordon Murray’s personal design process described by Cross in Chapter 2 as being “based on starting with a quick sketch of a whole idea, which is then developed through many different refinements.” Cross, op. cit., p. 51
10. Ibid., p. 75. Whilst examples of these three key strategic design aspects of design thinking being applied in architecture and urban planning are numerous, the proposal by Norman Foster for a new Thames Estuary Airport to serve as a major transport interchange in the UK provides a clear demonstration. Beginning with the ‘problem’ of airport capacity in the UK, Foster quickly takes a broad, systems-based approach to redefine the problem as one that must tackle issues of  rail, freight logistics, aviation, energy and its transmission, flood protection and regional development.  With the problem ‘reframed’ the design team then sets about providing a design solution based on ‘first principles’ that results in a highly integrated, innovative, design.
11. There is an interesting distinction here being made that implies ‘innovative’ design is the desired state of design and that which should be aimed for, a focus on bringing out ‘originality’.
12. Ibid., p. 73-5
13. The verbal account provided by the individual, ‘expert’, designer has some similarities the approach taking in design studio ‘crits’ wherein a tutor encourages a student to talk through a proposal and explain way they have taken certain design decisions. Unlike an interview  however the student and tutor are reflecting on the design and it is open to the possibility of change throughout the ‘crit’ The key difference here of course is that the ‘expert’ is being prompted whilst in the ‘act’ of designing, whereas the studio ‘crit’ is primarily concerned with review. This ‘reflective’ practice is dealt with by Donald Schön in “The Reflective Practitioner”, what is not clear from the experiment is how much the very act of ‘talking out loud’ encourages reflective action and as such could be seen to be ‘interfering’ with the ‘expert’ designers process of design thinking.
14. Ibid., p. 80 It is interesting to note that even after all of the observations made in the previous chapters design thinking is still regarded as being ‘mysterious’. This may in fact be more attributable to a commonly held belief (or misconception) that fails to take account of the growing body of evidence to support the opposite notion.
15. Ibid., p. p. 123-5 On Goel, Cross adds “…’as partial, interim ideas and solutions are generated, they are retained, massaged and incrementally developed until they reach their final form. Very rarely are ideas or solutions forgotten or discarded’.”
16. Ibid., p. 135
17. Ibid., p. 136
18. Ibid., p. 140
19. Ibid., p. 145
20. Ibid., p. 12
21. Ibid., p. 4
22. Ibid., p. 71
23. Ibid., p. 15
24. Ibid., p.. 69
25. Ibid., p. 26
26. Ibid., p. 73
27. Ibid., p. 2 He later goes on to add that “Teamwork is of considerable importance in normal professional design activity, and has become of even greater importance as design becomes a more integrated activity involving collaboration among many different professions.” p.91
28. Ibid., p. 20 Interestingly in design schools students often try to hide their design work at first and they have to be encouraged (learn) to accept outside influences.
29. Ibid., p. 20
30. Ibid., p. 118-9
31. Ibid., p. 119
32. Ibid., p. 111
33. Ibid., p. 72
34. Ibid., p. 146
35. Ibid., p. 74
36. Ibid., p. 147
37. Typical examples of this situation are cited when a winning design entry is said to ‘have broken the rules’. For example, BIG’s winning proposal for the new Danish Maritime Museum in 2007. happening
38. Cross, Op. Cit., p. 134-5
39. Ibid., p. 2
40. Ibid., p. 8
41. Ibid., p. 27
42. Ibid., p. 143
43. Ibid., p. 147
44. Ibid., p. 92