Very interesting article - the point is who's paying for the design? They will have a vested interest in persuading people to do something. The issue is one of responsibility and as a designer, whether you are going beyond persuasion and into the realms of deceit.

However, design is there to persuade. A pencil is a design that persuades you by showing you what it's for, what it's possibilities are and how easy it is to use - the persuasion is tiny, because you know it so well, but that persuasion exists all the same - I want you to use me to write and sketch.

Excellent article to which I have a few thoughts:
-Re: Pencil and Persuasion: Persuasion needs to be defined. Is persuasion the same as prompting, or stimulating something to be used a certain way? If so then a pencil design also persuades one to tap it, fire it with rubber bands, place it point up beneath the arms of arm wrestling contestants, etc.

- I wonder if perhaps there isn't a more holistic view here that needs to be adopted. There are similar discussions to this with regards to innovation and creativity (are they the same, different, how does one define innovation, etc.?) Perhaps dissecting the live frog on the table, with the end result that we'lll be flabbergasted the frog no longer jumps and lives at the completion of the process. Don't get me wrong, it's important for us to understand the processes involved, but there comes a point where the rubber needs to hit the road (Or the frog needs to jump and live) and the nuanced discussions, while great for exploratory purposes, might not get us where we want to be. If there were design thought churches, there would be schisms over this.

- Think of how many great designs of products or processes existed before the 20th century. There's a wonderful simplicity and elegance that is part and parcel of good design, something that touches us in ways that are persuasive as well as comforting - for the time being we like it as it is.

Persuasion exists indigenously without the intentions of anyone one let alone a designer. It is only intentional if one sets about with a goal for the persuasion. Even then they might accidentally persuade. Or, they might accidentally make a case for an unanticipate or undesired outcome. But, if you think you need intention to get convicted, rest assured that the procesutor will demand that your act implies intention.

Thanks Robert, this is a great piece and you certainly open up a lot of very interesting questions for anyone working in, or contemplating working in, this area of influencing behavior through design.

To clarify my (simplistic) "It's still user-centered if the behavior-influencing intent is aligned with what the user wants to achieve" argument, this still allows the same product/service to be experienced by different users, in different contexts, with different needs and desires, in different ways. In some circumstances it will provide a good user experience, other times it won't.

If, as a user, I just want an exercise bike that lets me exercise, getting one which continually 'motivates' me through sound effects and setting me targets, which I can't switch off, is not user-centered design from my point of view. Yet for the person next to me, that might be exactly what they want and need. A design can surely be user-centered with respect to some users and not with others. The 'user-centered' aspect only exists if there are actual users using the thing - and since we can't design things that fulfill everyone's needs, all the time, there will (as with anything) be combinations of needs, circumstances, attitudes where it works, and others where it doesn't.

People change, too. Think of 'tip of the day' splash screens in software. It might be great user-centered design for many (most?) users to start off with, helping them learn more about what they can do, and influencing greater engagement with the program. But many people uncheck that 'Show at startup' box pretty quickly. Their needs have changed: it becomes a nagging annoyance rather than aligning with what they want to achieve at that moment (getting on with the task). As long as the interface allows you to switch it off, that in itself is a largely user-centered design consideration. A designer had to think 'Some people won't want to see this every time' and create the affordance of disabling it (and re-enabling it, too).

To take your Project Masiluleke as a example: for the people who've responded in the way you hoped as designers, i.e. gone and got themselves tested, changed their behavior, the suggestion the messages made clearly aligned with something those people wanted. The persuasion worked, whether it was kairos (B J Fogg) or pushing an open door, or making them think about something they'd never felt able to do, or leveraging the emotional affect associated with receiving a missed call from a loved one, or something else. For them, this was an experience that touched (/nudged) them in some way: it was centered on them, as users. For others who ignored it, or didn't feel able to commit to go and get checked, the experience clearly wasn't aligned quite enough with their current state (needs, desires, what they will admit to themselves even). Maybe it will be in the future, or maybe different strategies are needed, but overall the project is still a great success because it's influenced the behavior of a lot of people.

Someone said to me the other day that the best advice he'd had (in an academic context) was "Don't make a distinction that doesn't do anything for you" (in terms of classifying things, ideas, concepts). Maybe that's true here - I think between us, we are all trying to achieve the same goals. I too often get tangled up in trying to define things because it seems like that's what's required academically, whereas wearing my designer hat (not literally!), I know full well that what matters is what works, and getting those insights about users' understanding, motivation and mental models, and working out a way of applying them through design to help people, is far more important that worrying about what 'sort' of design we're doing.

thank you! i was super interested in this topic, along with your "design to change behavior"discussion. great article and discussion! i'm learning a lot.

so i kinda define persuasive design here in a broad way: hint, affect the perception, stimulate, market & mind control.

hint:
the first time i got drawn into this topic was when doing industrial design years ago: to design a handle that hints users to hold and pull in certain way, using the form, the details, and the accordance. it's not exactly persuasive design, but definitely where i came from when designing other stuff that persuades people.

affect the perception:
the second time was when doing a concept design on electricity-meter to save energy (http://itp.nyu.edu/~ml1949/Energy.htm). Since the energy doesn't have its form and weight, so we perceive the energy as air, plenty, endless, so in a very natural way, we waste them, we just don't care. if we see them as money or milk that is the material consumed with limit, probably we can change our way of using them. so that design was using the concept of both clock and teapot, aiming to make people to re-read energy, persuading them to not waste, changing their behavior day by day. it was 5 years ago, it was not a great design as a whole. but i do think it is relevant to changing behavior by design.

stimulate:
when nike + came out, same year, intel research people put out a project, persuading teenage girls to lose weight by designing a social exercise mobile game, both projects are stimulating users to change behavior. similar things, e.g. 12steps. i believe designers are using design tricks: design thinking and practices to persuade people to change their behavior.

market:
then about design and marketing, there is a type of design, no matter a product, a service or/and a policy, it is not to solve problems, but creating new opportunities based on new technological & socioeconomic phenomenon. there's no need from end users until the design out there, people starts using them, so how to persuade people to use is important, which is marketing.

mind control:
Hitler is a pretty good persuasive designer, but with some evil motivations.
i see persuasive design is a skill that designers should be trained to obtain. it's a tool without negative/positive effects, until adding designers' motivation, why do we want to persuade people? for solving a problem? for money?for losing weight? for saving the energy? for helping a company to innovate? OR for starting the second world war?

just throw out my 2 cents, hoping to learn more from you guys here. (hit me if u r hiring :-) )

A few thoughts I posted on Jamie's blog I can't resist offering to you too:

I think the idea that things inform behaviour is sure, and needs to be expressed. That takes things beyond ‘the price of everything and the value of nothing’.

I think the Industrial revolution has stunted the value side and the holistic health of people in their interactions with the world; at it’s height a person bought a hifi mainly for specification with little experiential motivation. That I think was a product of both the Enlightenment and the Industrial Revolution, rationality dominance and spreadsheet thinking.
So to the designer’s role… I feel like to repair the relationship between Industry and people is to empower people rather than to change them. I feel like people are looking for transformation, they desire fullness, so they will seek it. The path of design has added transformation to experience to specification and technology innovation before that, but I feel like that’s industry maturing to the point of recognising consumers rather than maturing to the point of dominating/leading them.

In this new role designers need to know consumers, holistically, empathising, advocating. I’m trying to steer away from asking is design a value system in the sense that value is out there.

So to the State’s role… I think it needs design thinkers in the mold I’ve described.. It needs to engage with the narrative, with the intangibles to find the stories on the street.