Commitments, Towels, and “Two for One” Influence


 by Steve Martin, August 2012

Inside Influence Report regulars as well as readers of the book Yes! will be familiar with the wonderful series of studies conducted by Noah Goldstein, Vlad Griskevicius and Robert Cialdini examining which messages are most effective at persuading hotel guests to reuse their towels during a stay. (For those who aren’t, towel reuse rose by 26% when hotel guests were told, via a little card placed in bathrooms, that the majority of previous guests do reuse their towels).

These experiments have been widely cited in the academic, business and popular press and so when presenting them in talks and workshops I will occasionally encounter folks who are already aware of them. When that happens I might ask the group to think about how other principles of influence might be employed to encourage towel reuse. For example what would happen if a guest was asked to make a commitment to support environmental efforts before they had even reached their room, such as during the check in process?

This has always struck me as an interesting idea but to date there has been no empirical data measuring such an approach. Until now!

Researchers have been recently testing this exact idea and although the studies won’t be published until next year, Inside Influence Report readers can be amongst the first to learn about the results as well as implications they might have for your future influence attempts. 

Click here to read more

Over a one month period a team of researchers from the University of California arranged for guests checking-in to a popular Californian hotel to be asked to make a commitment related to environmental protection.

In some instances the commitment requested was a general one; please check this box indicating your willingness to be environmentally protective during your stay. In other instances the commitment requested was a more specific one; please check this box indicating your willingness to reuse your towels during your stay.

In addition to asking for either a general or a specific commitment some guests were also given a ‘Friend of the Earth’  pin badge. These badges were also given to a number of other guests who had not been asked to make a commitment when they checked into the hotel to test whether simply being given a badge to wear would influence their behavior.

Finally a control group of guests were simply checked-in in the normal fashion and were not given a pin badge or asked to make a commitment.

So what happened?

Well the first thing that the study looked at was the percentage of guests who were actually willing to make a commitment and it turned out to be pretty high. Some 98% of guests in the general commitment group were willing to make a commitment, and even though the number of guests willing to make a more specific commitment was lower, it was still impressive with 83% checking the box. So at first glance, it seems that when attempting to persuade an individual to make a commitment, you might increase your chances of success by asking them to make a general rather than a more specific commitment.

Of course that begs another question. Which commitments are more likely to be lived up to; general commitments or specific ones?

As far as this study is concerned there was a clear answer. Guests who made a specific commitment at check-in were more likely to reuse their towels than the guests who made a general commitment (66% v 61%). Perhaps more interesting was the finding that guests who did make specific commitments to reuse their towels were also more likely to adopt other environmentally protective behaviors that were consistent with that initial commitment. For example they were more likely to turn off the lights, turn down the air conditioner unit and switch off the TV when leaving their room.

This latter finding might be an especially important insight to those of us who have the challenge of influencing multiple related behavior changes in others, highlighting a potential two-step approach. Step one will be to ensure that the initial commitment you seek is a specific one. Step two will be to arrange for the environment where that commitment will be enacted to include cues that could trigger other related and desirable behaviors consistent with that initial specific commitment.  

Let’s take an example. Imagine that as the manager of an office facility you have the challenge of not only encouraging more recycling but also to reduce your general energy costs. This finding suggests that you should first ask office workers to make a specific commitment to one behavior (let’s say to place paper in the recycling bin as they leave the office at night) and then position those recycling bins in a place that could activate related behaviors that will reduce energy costs (let’s say next to a light switch). In essence a “two outcomes for the price of one request” influence strategy.

And what of those pin badges? Well as you might expect, guests who made a commitment and who were also given a badge were even more likely to reuse their towels than those that had just made commitments. They were also the most likely to engage in other environmentally protective behaviors while staying in the hotel suggesting that the little badge serves two important purposes. First it serves as a reminder to the individual of the commitment they have made. Secondly it serves as a signal to others of that commitment.

Interestingly the guests who were provided with a pin badge but were not asked to make a commitment were the least likely of all to reuse their towels. They were even less likely to reuse their towels than guests who weren’t part of the study at all.

This is consistent with Cialdini’s research showing in order for commitments to stand the best chance of being lived up to they need to be owned by the person making them, as well as being action-orientated and public. Accordingly, when persuading others to live up to their commitments a detective of influence will make arrangements for those commitments to be volunteered as well as stated specifically before providing ways for their target to publicly signal them too.

Of course it is rare for a business to encounter solely external influence challenges such as persuading customers and clients. Invariably some challenges businesses face will be internal, for example persuading employees and associates to change their behavior.

This was certainly the case with the hotel in this study whose housekeeping staff would often replace towels even if guests had indicated that they wished to reuse them. But perhaps the best strategy to persuade housekeeping staff to comply with appropriate towel replacement is exactly the same as one used to persuade guests to comply with appropriate towel reuse. Namely to gain a specific commitment and then provide a way of publicizing that commitment. An example of a ‘two for one’ influence strategy.



If you were a hotel manager how might you effectively and ethically employ any of the principles of influence to encourage towel reuse? (I can’t promise but maybe we’ll end up studying some of the best suggestions!)



Baca-Motes, K., Brown, A., Gneezy, A., Keenan, E.A., & Nelson, L.D. Commitment and Behavior Change: Evidence for the Field. Journal of Consumer Research DOI: 10.1086/667226 (forthcoming)

Cialdini, R.B., Influence – Science and Practice 5th Edition ( 2009) Allyn & Bacon. New York


Goldstein, N.J., Cialdini, R.B., & Griskevicius, V. (2008). A Room with a Viewpoint: Using Social Norms to Motivate Environmental Conservation in Hotels. Journal of Consumer Research Vol 35: 3, pages 472-482


*And for those of you wanting even more information…..

The Goldstein, Cialdini, and Griskevicius article referred to by Seve Martin above is A Room With A Viewpoint.

The Journal of Consumenr Psychology awarded this article the best paper of the year.   And recently Emerald Reviews awarded this paper the Citation of Excellence for 2012 saying, “A Room With a Viewpoint: using social norms to motivate environmental conservation in hotels” (Journal of Consumer Research, 2008) was chosen because of its proven impact since its publication date (2008 in this case, to allow for citation impact to be accurately measured) from the top 300 management journals in the world.

Hooray for Science!

  • Manuel

    very interesting, but I see that the majority of this “hotel study” are made in USA hotels.
    It’s possibile that different nationality of hotel guests give different results?
    for example, that american hotel guests are more influenced by the re-use of towels, instead of german, or japan guests?
    or maybe that 4 stars hotel guests are more influenced instead that hotels with fewer stars?

  • Vincent van der Lubbe

    1. Authority = default. What about inverting it: make reuse the default. Place a surcharge like Ryanair on extra towel? In youth hostels you have to bring your own towel, for towel and sheets there is a surcharge. Probably works only for budget hotels.

    2. Help people to place the mat somewhere so it can be reused. Mat = on the floor. On the floor means often =I want a new towel. I have tried to hang the mat over the bathtub to indicate it is not on the floor, so should be reused. Didn’t work most of the times. Saving: Make quick calculation of number of mats x days = a lot!

    3. Make rest of room/bathroom more “environmentally” friendly. “Ambient” persuasion helps with consistency? How do plastic shampoo bottles, showercaps etc. help or not?

    4. Commitment: reciprocity. A thank you note after reuse. How does this affect reuse? Peo

    5. Commitment: show consequenes. Add number of how much is actually saved (litres or mesningful comparison) like the number of about 100 litres of polluted water for one cigarette butt in the water.

    • Steve_Martin

      This is a great list of ideas, thanks so much for contributing. I think your comment about making a simple set of wording available is especially important . Last week I stayed in a hotel that had cards that offered points for reusing towels and linens. Not only was the order of the offer (if you resue then we pay) likely to be ineffective the system was so complex that guests where then alerted to a full page of conditions that had to be met in order to qualify – it was so complex. If ethcially influencing behaviours means using the prinicples to go with the grain of how people like to make decision then the one I saw seemed to go against pretty much all of them.

  • Vincent van der Lubbe

    6. Often rooms are double rooms with a double set of towels. If the room is booked by one person, one could often spare one set. Default: one set.

    7. Make a simple set of the wording available, so committed hotel guests can educate their hotel staff in case the signs are not in place yet :-)

    • Brian Dickens

      I think this is a great point…how much savings and environmental benefit would be realized if housekeeping simply removed at least two extra towels from rooms that are booked by single guests, or better yet, stocked all rooms with only two towels and only delivered additional towels when requested by the guests?

  • Louise

    I would be very interested to see any studies where participants are being asked to make commitments to do things that are much harder than re using towels. Does this approach work to help people loose weight, give up smoking or increase their exercise?

    • Steve_Martin

      Bobette is absolutey right about people’ desire to be consistent with previous commitments (particulary effortful and public ones) being a good basis for other behaviour change programs such as weight loss and exercise. I would add that commitments made up of incremental small steps that lead toward a symbolic goal will be best. There’s some new research about to published on this which I am currently reviewing for a future Inside Influence Report so keep watching.

  • Jim Campain

    I am fascinated with the impact of marketing peer norms. Have been using it successfully past several years in schools with such issues as attendance, graduation rates, bullying-related behaviors as well as many substance abuse issues. Behavior clearly changes/improves when students realize their healthy attitudes and behaviors reflect the majority of thinking and acting by others. Tough to get school administrators out of the “same old-same old” prevention and school improvement efforts. Would welcome opportunity to share 10 years of experiences/data for the new Yes! 2.0.

  • FundraisingProfessor

    Public commitments help. Could guests be given a small sign (or sticky note) to put on the outside of their room door that says either “I support the environment and I’ll reuse my towels” or (flip side) “Please replace my towels. This would serve three purposes.

    1. It makes a very public declaration at the site, possibly shaming people into compliance

    2. Seeing signs on other doors might encourage crowd-influenced behaviour (management could even put the towel-saving sign on unoccupied rooms to make it seem like there are more, but would that be ethical?

    3. It would remind room service staff of the choice the guest had made.

  • Jim Campain

    Yes, Louise, we have applied the power of influence in over 60 schools and communities across the country with critical issues such as underage drinking and driving, school attendance and graduation rates, parents supporting parents, stress among high school students and rumor spreading and trash talk among middle school students. When participants in the studies learn that the behavior of their peers is healthier than they predict, they tend to model the healthy behaviors, just as in the “towel” study.

  • Lael Thompson, Denver Colorado

    Perhaps the guest could be provided with a distinct type of towel durring their stay, if they agreed to reuse. This would provide a similar effect to the lapel pin, but it would be in the room and directly reminding them of their commitment when the action for re-use in required. It would also make it clear to the housekeeping staff which towels to replace and which ones to leave behind.
    Since every hotel has multiple towels in the room, one or two of those towels could be the unique ones. Maybe a logo or color…

  • Rob Spurlock

    I love to read about these studies. Thanks Steve.

    • Steve_Martin

      You’re very welcome Rob. And please do keep the comments coming. We appreciate them very much.

  • Ben Drake

    How about asking the individuals to write their name on a board or “Wall of Environmentalists.” Thus creating a “consistent” public commitment, that provides “social proof” to future hotel guests who are “like” each other.

    Plus, studies have shown that rewarding actions that individuals might have taken without the reward, removes the intrinsic motivation and makes them less likely to do it again in the future, especially without a reward. Instead of offering worthless tokens or badges, provide a donation, in the name of the hotel guests who sign the wall, to an environmental charity of their choice in the amount of dollars that a reused towel will save the hotel.

    Something like, “Sign your name on the wall of environmentalists and Hotel XYZ will donate $5 per nights of stay to your choice of these great charities: x, y, z. Help us save the environment – One Towel at a Time.”

    This will provide the benefit of the hotel guest feeling “reciprocal” for having enabled a donation to a worthy cause AND will take their mind off the fact that the hotel isn’t just trying to save money by masquerading as environmentally friendly. If you want guests to be environmental, the hotel should “put their money where their mouth is.”

    I think I addressed as many of the PoP as possible….

  • Eily

    Absolutely. That’s why every effective weight loss program has you write down your goals. This is a very powerful principle of influence. It’s important to remember that people have a strong internal drive to be consistent with their own prior commitments. You can always look at Dr. Caitlin’s book in the chapter on consistency for more research, details and stories. Or, take a look at this piece. It’s well written and chock full of examples,
    Bobette Gorden

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