1. Commitments, norms & the £1billion tax letter STEVE J MARTIN

2. “It turns out that the environmental and context effects on behaviour and decision making are a lot stronger than most people expect.” Danny Kahneman, 2008

3. Principles of Social Influence Reciprocity Authority Social Proof Scarcity Consistency Liking “Yes! 50 Secrets from the Science of Persuasion”, N.J. Goldstein, S.J. Martin, R. B. Cialdini Published by Profile Books (2007)

4. Principles of Social Influence Reciprocity Authority Social Proof Scarcity Consistency Liking “Yes! 50 Secrets from the Science of Persuasion”, N.J. Goldstein, S.J. Martin, R. B. Cialdini Published by Profile Books (2007)

5. People underestimate the influence of social proof Reported Beliefs Regarding the Influence of Each Motive Descriptive Norm Saving Money Benefit to Society Environmental Protection 2.9 3.0 3.1 3.2 3.3 3.4 3.5 Different Motives to Conserve Energy Environmental Protection Correlation of Each Motive with Conservation Behavior.00.10 Descriptive Norm Saving Money Benefit to Society.50.40.30.20 Schultz, W.B., Cialdini, R.B.,et al (2007) “The constructive, destructive and reconstructive power of social norms” Psychological Science, 18:429-34.

6. Hotel Towel Reuse Study

7. Hotel Towel Study Environmental AppealMany Others

8. 50 20 25 30 35 40 45 Environmental Appeal % Towel Reuse Rates 35.1% 46.0% Many Others

9. Hotel Towel Study Environmental AppealMany Others Many Similar Others

10. 50 20 25 30 35 40 45 Environmental Appeal % Towel Reuse Rates 35.1% 46.0% Many Others 53.1% Many Similar Others

11. OK, so it works for towels! But what about Taxes?

12. 80 50 55 60 65 70 75 Control Group % Tax Return Rates 67.5% 72.5% Social Norm National 79.0% Social Norm in your postcode 82.9% Social Norm in your town

13. Principles of Social Influence Reciprocity Authority Social Proof Scarcity Consistency Liking “Yes! 50 Secrets from the Science of Persuasion”, N.J. Goldstein, S.J. Martin, R. B. Cialdini Published by Profile Books (2007)

14. 10 -30 -20 -10 -5 0 5 -18.0% Active Commitment -3.4% Verbal Commitment Martin, S.J., Bassi, S., Dunbar-Rees, R., (2011) Commitments, Norms & Custard Creams - A social influence approach to reducing Did Not Attends (DNAs) Journal Royal Society of Medicine (in press) Healthcare Did Not Attend Studies

15. Principles of Social Influence Reciprocity Authority Social Proof Scarcity Consistency Liking “Yes! 50 Secrets from the Science of Persuasion”, N.J. Goldstein, S.J. Martin, R. B. Cialdini Published by Profile Books (2007)

16. The Big Mistake To encourage corrective action against a problem that is large or growing, leaders and policy makers often decry that problem as regrettably frequent. Expenses Fraud Tax Avoidance Littering Binge Drinking STD Infections Teenage Pregnancy “Yes! 50 Secrets from the Science of Persuasion”, N.J. Goldstein, S.J. Martin, R. B. Cialdini Published by Profile Books (2007)

18. --31.4% Commitment + Normative Appeal 10 -30 -20 -10 -5 0 5 -18.0% Active Commitment -3.4% Verbal Commitment Martin, S.J., Bassi, S., Dunbar-Rees, R., (2011) Commitments, Norms & Custard Creams - A social influence approach to reducing Did Not Attends (DNAs) Journal Royal Society of Medicine (in press) Healthcare Did Not Attend Studies

19. Leaders and policy-makers may focus too often on economic, legal or policy factors when seeking to motivate people towards desirable goals They would be well advised to also consider what is known about social psychological motivators such as social norms, social obligations, source credibility and loss aversion as well as multiple other motivators (MINDSPACE) There is an increasing need to incorporate what is known from social sciences into behaviour change programmes – methodologies and programmes exist to assist in making that happen