Paul Hekkert

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Paul Hekkert is professor of Form Theory at the department of Industrial Design of Delft University of Technology. His main research interest is product experience, including product aesthetics, emotion, expressiveness, and attachment. Next, he is involved in design methodology and has co-developed an interaction-centred design approach, called ViP (Vision in Product design).

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Hekkert, Paul, Snelders, Dirk, Wieringen, Piet C. W. (2010): "Most advanced, yet acceptable": Typicality and novelty as joint predictors of aesthetic p. In British Journal of Psychology, 94 (1) pp. 111-124.

Hekkert, Paul, Mostert, Marc, Stompff, Guido (2003): Dancing with a machine: a case of experience-driven design. In: DPPI 2003 - Proceedings of the 2003 International Conference on Designing Pleasurable Products and Interfaces June 23-26, 2003, Pittsburgh, PA, USA. pp. 114-119.

Russo, Beatriz, Hekkert, Paul (2007): On the experience of love: the underlying principles. In: Koskinen, Ilpo, Keinonen, Turkka (eds.) DPPI 2007 - Proceedings of the 2007 International Conference on Designing Pleasurable Products and Interfaces August 22-25, 2007, Helsinki, Finland. pp. 12-19.

Alonso, Miguel Bruns, Varkevisser, Michel, Hekkert, Paul, Keyson, David V. (2007): Exploring Manipulative Hand Movements During a Stressful Condition. In: Paiva, Ana, Prada, Rui, Picard, Rosalind W. (eds.) ACII 2007 - Affective Computing and Intelligent Interaction, Second International Conference September 12-14, 2007, Lisbon, Portugal. pp. 757-758.

Russo, Beatriz, Boess, Stella, Hekkert, Paul (2008): Talking about interactions: Eliciting structured interaction stories in enduring product e. In: Proceedings of the 6th Design and Emotion conference October 6-9, 2008, Hong Kong, Hong Kong.

Russo, Beatriz, Hekkert, Paul (2008): Sobre amar um produto: Os principios fundamentais. In: "Design Ergonomia Emoçao" Mauad .

Russo, Beatriz, Boess, Stella, Hekkert, Paul (2009): Assessing interactions in enduring product experiences: The EXITool. In: Proceedings of the 17th World Congress on Ergonomics, IEA2009 August 9-14, 2009, Beijing, China.

Hekkert, Paul

12.5 Commentary by Paul Hekkert

Affective computing is an exiting discipline and Kristina Höök offers us some nice examples of what the field can bring. Wouldn't it be great if intelligent machines could somehow 'sense' what we feel when interacting with them and then adjust their actions accordingly? This is actually what the pioneers of affective computing saw as their challenge and this is what they have been after:

1. Is it possible to recognize people's emotional responses/states from their behavior, physiological responses or facial expressions, and
2. Can we make the system (e.g. computer, product, mobile device) take this information into account in appropriate responses? Rosalind Picard will correct me if I am wrong that these were and still are the main challenges of the AC discipline.

Is this reductionist? Sure it is, you can only measure a few indicators of people's emotional responses and each and every indicator (e.g. pressure exerted, skin conductance, heart rate variability, facial muscles) only tells a little part of the story. There are many behavioral, physiological and psychological sides to an emotion and we simply cannot tap them all. But what is the alternative? We want our measurements to be as non-invasive as possible. If we end up affecting people's behavior or even change their emotional states because of the way we are measuring, the whole purpose is lost. Preferably, we measure user's emotional responses without them being aware of it. The question is what each and every indicator of an emotion actually tells us (its validity) and how accurately – and unobtrusively – we can measure it. A lot of the work in AC has been put into these questions.

As an alternative, Kristina Höök proposes the "Interactional Approach" where the system allows users to reflect on their emotional experiences. This, however, does not eliminate the measurement problem as we can for example see in the "Affective Diary". This application registers movement and arousal as indicators of people's emotional state and transfers these data into shapes and colors as a form of feedback. If you aim to give people feedback on their feelings this is the 'appropriate response' you decided on and you have moved to the second challenge of AC: how to respond? And of course, the response you aim for very much depends on the type and function of the system. When I am typing a document in Word – as I am doing now – I do not want the system to give me continuous feedback on my emotional states, nor do I want to see these reflected in the words I type. But I may want the system to recognize that I am in a hurry, or impatient, or stressed, and subtly 'make me' slow down, without me being aware of it. Miguel Bruns Alonso recently explored this idea in the design of a pen that senses implicit behaviors related to restlessness and responds by providing inherent feedback to lower the stress level (Bruns Alonso et al., 2011).

So, is there an alternative to the measurement problem? In another example from Kristina Höök's chapter, she describes eMoto, an extended SMS-service that allows people to communicate their feelings in colorful and animated shapes. This type of 'measurement' – making users express their own emotions in words or images – only works when we are dealing with communication devices and is problematic for different reasons. First of all, it is obtrusive and not very recommendable if communicating emotions is not the design goal. But also, there are validity problems in people's verbal or non-verbal reports of their own emotions. All kind of social rules, demand characteristics (of the device?), and response styles may interfere with a valid report of your own feelings (see e.g. Mauss and Robinson, 2009 for a review of emotion measures).

And yes, I fully agree with Kristina that the role of our body is relatively unexplored in the AC field and offers a lot of potential, both to the recognition and response challenge. Given recent advances in cognitive science (see e.g. Johnson, 2007), where bodily experiences are increasingly recognized as being at the roots of our thinking and feeling, we may expect more and more studies – like Bruns Alonso's – in which our body is the main mediator. How else can we "grasp" the affective domain?


  • Bruns Alonso, M., Hummels, C.C.M., Keyson, D.V., & Hekkert, P. (Conditionally accepted). Measuring and adapting behavior during product interaction to influence affect. Personal and Ubiquitous Computing.
  • Johnson, M. (2007). The meaning of the body: Aesthetics of human understanding. Chicago: The University of Chicago Press.
  • Mauss, I.B. & Robinson, M.D. (2009). Measures of emotion: A review. Cognition and Emotion, 23, 209-237.

Hekkert, Paul

3.11 Commentary by Paul Hekkert

Everything I read in Marc Hassenzahl's chapter sounds so true, so valuable, and so familiar. It comforted me, and it puzzled me. Of course, designers are there to shape experiences. Nokia, or any mobile phone manufacturer, is all about connectedness, not about these mobile devices. All design starts with a 'why', and next comes the 'what', or the 'how'. I will come back to this order in a minute.

Recently, I published a new book together with designer and colleague Matthijs van Dijk: "Vision in Design: A guidebook for innovators" (2011). It spends over 300 pages on explaining (future) designers on how to find the WHY of their designs, what we call its 'raison d'être' or 'Daseinsgrund'. The reason of existence is grounded in the future world, as the designer sees it, and reflects what the designer wants to offer people given this world. What do you want people to understand, see, be able to, feel or experience? This goal or ultimate reason is indeed often experiential1. A random example from a student: "I want passengers to experience a sense of freedom within the limited space of an aircraft, by stimulating mental travel." This experiential goal takes into account the context of an aircraft, the mental state people are in during traveling, social anxiety, and people's love of mind wandering. This ultimate experience comes first; the product is (just) instrumental in realizing it. Or as Marc puts it: it's all about bringing "... the resulting experience to the fore - to design the experience before the product." Hence the familiarity.

It is so obvious and logical and yet Marc has managed to phrase it in a way that is crisp and clear and thereby he opens it up to an audience that may not seem so aware of its logic. People who are caught up in technological advancements for their own sake? And here Marc also puzzles me. Why this emphasis on interactive products? All products are – in essence – interactive, they allow for and require interaction, and all products can contribute to, stage, shape, facilitate, or enable experiences. Think of Starck's Juicy Salif, designed to stimulate conversations between a son- and mother-in-law. Or the example of the bucket "... a bucket is not a typical exemplar of an interactive product", as Marc writes. So what?

Somewhere along the line, the 'why' must be transformed in a 'what' and a 'how' and I believe the crux is in changing the order Marc proposed. After the WHY, designers should not immediately follow with a WHAT, but first decide on the HOW. This HOW is the user experience or product experience as we have coined it (Schifferstein and Hekkert, 2008); it captures the way people will interact with and experience the to-be-designed product that is not yet defined. These qualities of the interaction are intangible and not bound to anything, and they determine whether the ultimate experiential goal will be met. The WHAT that is next to be designed is simply a carrier of these qualities and it can be any type of product, an interactive product, a service, or a web application.

Let us consider an example of how this works. Years ago, student Sanne Kistemaker defined the experiential goal (the WHY) of her design project as "I want people to experience sarcastic triumph while staring at other people". We all want this, right? Watch other people while on the train, see what habits they have composed, see how they interact each other. She could have easily solved her design goal by some augmented reality type of application on a smart phone. But before she decided on the 'carrier' of her experience, she first defined what the interaction with the product should be. This interaction, as she saw it, should be tricky, reluctant, apprehensive, and straightforward, to make the user feel guilty and hesitating, yet proud and rebellious. She designed this interaction and corresponding user experience without having a clue what product should do this. And she beautifully solved it without any technological means: a newspaper that is offered with a small hole in the middle (see Figure)2. You may hesitate to use this paper, it is a little tricky, but once you do, in a train or on a terrace, you will certainly feel guilty and probably experience a sarcastic triumph!

Figure 3.1
Figure 3.2

To sum up, Marc importantly stresses that the user experience, the experience of the (interactive) product, should never be an end in itself, but is always instrumental to some life experience. All very true. And since the final design, the product, is again instrumental to the user experience, it seems only logical to make this the order of things: ultimate experience (WHY) > user experience (HOW) > product (WHAT). Designing along these lines is exactly what Verganti (2009) means when he speaks of 'design-driven innovation', where the designer pushes a new meaning, a new experience onto the public. Marc's chapter gives us many clues on how to do this.


Hekkert, P. & van Dijk, M. (2011). Vision in Design: A Guidebook for Innovators. Amsterdam: BIS.

Schifferstein, H.N.J. & Hekkert, P. (Eds.)(2008). Product Experience. Amsterdam: Elsevier.

Verganti, R. (2009). Design Driven Innovation – Changing the Rules of Competition by Radically Innovating what Things Mean. Boston, MA: Harvard Business Press.


  1. When we look at public products for instance, the underlying reason can also be behavioral. Designing for behavioral change is currently a popular topic in design research.
  2. Itis crucial for the design that the whole is already there; the experience would fail if the user had to make his/her own hole.

Schifferstein, Hendrik N. J., Hekkert, Paul (2007): Product Experience, Elsevier Science,

Hekkert, Paul

17.10 Commentary by Paul Hekkert

Designers talk a lot about innovation and every designer wants to be an innovator. Well, most... Christensen sketches a few trajectories along which a company can innovate and this is a great analysis for business people, managers, and decision makers, because he meticulously explains the conditions under which a disruptive innovation might fail and succeed. Since most companies (luckily) rely more and more on designers to drive this innovation process, he also shows designers where and how they can make a difference.
If you read carefully.

Designers who just have a superficial knowledge of the innovation literature may be a bit puzzled.  They may be familiar with the distinction between incremental – making existing stuff a little better (we will come back to this ‘better’) – and radical or breakthrough – coming up with a completely new product type or category – innovation. Christensen proposes a completely different distinction between sustaining and disruptive innovations. Both can be incremental and both can be radical, it all depends on their effect on the established businesses and mainstream markets. And Christensen talks about companies, technology and the absorption capacity of customers. Design, or the designer, is non-existent in his scheme of things. Let’s see if we can fit him or her in somewhere.

To explain how innovations can disrupt markets, Christensen contrasts these disruptions with sustaining innovations. So-called high-end customers continuously demand “better performance than what was previously available”. Do they? Clearly, designers can make products perform better: faster, more reliable, more sustainable, more efficient, more user-friendly, etc. This can be a small step (incremental) or a big step (breakthrough). Key is that the innovation sustains the current market and the better product can be sold with higher margins. A nice example is the (Dutch!) Senz umbrella. In a market that seemed completely satisfied, the designers came up with a radically new umbrella concept, an umbrella that is stormproof, requires a different interaction (pull instead of push to open), and looks and feels different.

The SENZ umbrella, developed at the Delft University of Technology, withstanding stormy winds. Picture taken at the Kunsthal exhibition on Dutch Design.
Figure 17.1: The SENZ umbrella, developed at the Delft University of Technology, withstanding stormy winds. Picture taken at the Kunsthal exhibition on Dutch Design.

When it comes to disruptive innovations, Christensen makes an interesting distinction between low-end disruptions and new-market disruptions. Low-end disruptions, to begin with, typically involve cheaper, simpler, and more convenient alternatives to existing products. A nice and relatively recent example from his chart is (and equivalent internet bookstores) that slowly and gradually disrupt traditional bookshops. Although I know of designers who take pride in coming up with clever, cheap and low-fi alternatives for available products, it is not the kind of innovation many designers would strive for. These alternatives are foremost attractive from a business perspective.

It is the new-market disruptions that appeal to most designers – at least those that strive to be innovative. These innovations initially address new markets and new customers and gradually invade (and disrupt) the mainstream market. I however wonder whether (a low) price and ease of use, as Christensen claims, are also the only and defining qualities here. Take for example the highly acclaimed iPad. It certainly started to attract many new customers – well, who was new in this market? – and gradually started to compete with laptops and notebooks. But was this because it is a cheap or easy to use product? Maybe so, but foremost the iPad allowed for a completely new and compelling way of interacting with media and information. There is much more to (using the) iPad than price, functionality, and convenience; the iPad offers us a new experience, one that is compelling, engaging, cursory, and fun. Not only for individuals, but also for families!

The iPad offers us a new experience, one that is compelling,  engaging, cursory, and fun
Figure 17.2: The iPad offers us a new experience, one that is compelling, engaging, cursory, and fun

In his excellent Chapter on Experience Design, Marc Hassenzahl argues that this is what designers can and should do: define and create new experiences. For this, as I indicated in my commentary to his chapter, and by referring to books by Verganti (2009) and myself (Hekkert & van Dijk, 2011), designers should not follow a demand from the market. Rather, they should push new markets by offering new meanings, new values, in ways that people never imagined would be possible. Interactive technologies and new media are the carriers par excellence to embody these new meanings. More and more companies start to acknowledge the power of design to drive new-market innovations that may turn out to be disruptive.

17.10.1 References

  • Hassenzahl, Marc (2011). User Experience and Experience Design. In: Soegaard, Mads and Dam, Rikke Friis (eds.), Encyclopedia of Human-Computer Interaction.
  • Hekkert, P. & van Dijk, M. (2011). Vision in Design: A Guidebook for Innovators. Amsterdam: BIS.
  • Verganti, R. (2009). Design Driven Innovation – Changing the Rules of Competition by Radically Innovating what Things Mean. Boston, MA: Harvard Business Press.