| QUICK ANSWER |
| Temptation bundling, developed by Katherine Milkman at Wharton, pairs immediately rewarding activities with behaviours that produce long-term benefit but lack immediate appeal. Commitment devices, studied by Ariely and Thaler, involve advance arrangements that restrict future choices against present bias. Both are among the most research-supported practical applications of behavioral economics. They work by changing the choice environment in advance rather than fighting temptation at the moment it occurs. |
Table of Contents
Self-control failures are the norm rather than the exception. Most people intend to exercise, save more, eat better, and complete important work. Most people also find, repeatedly, that these intentions dissolve when the moment arrives and the immediate alternative is more compelling. The behavioral economics research on self-control has produced two interventions with strong evidence that take a different approach to this problem: rather than trying harder at the moment of temptation, they change the structure of the choice before that moment arrives.
Temptation bundling and commitment devices work through different mechanisms but share the same core insight: fighting temptation at the moment of occurrence is the least effective strategy available. The present-biased self who needs to exercise is not the same self who decided, in a cooler moment, that exercise is important. Designing for the moment of temptation rather than hoping the cooler self’s preferences will win is more reliable and more sustainable.
Temptation Bundling: Milkman’s Research
Katherine Milkman and colleagues at the University of Pennsylvania designed temptation bundling as both a concept and a tested intervention. The core principle is simple: restrict access to an immediately rewarding activity you want to consume (an engaging podcast, a favourite series, a pleasurable novel) exclusively to the context of a beneficial but intrinsically unrewarding activity you need to do (exercise, administrative work, a tedious commute).
The field experiment Milkman ran at a university gym tested this directly. Participants randomised to receive iPods preloaded with compelling audio novels they could only access during gym sessions showed significantly higher gym attendance over nine weeks than control participants. The bundle made attending the gym the only available path to the immediately rewarding experience, collapsing the temporal gap that present bias exploits. Both the cost and the reward were delivered in the present.
The restriction element is essential. Milkman’s research found that participants who could access the novels at any time showed smaller attendance improvements than those with restricted access. Freely available temptations lose their bundling power. The technique requires genuine restriction: the reward must not be accessible except through the bundled activity.
| RESEARCH NOTE: Milkman et al. Gym Study |
| Milkman, Minson, and Volpp (2014) randomised gym members to either receive iPods preloaded with novels available only at the gym, receive similar novels without restriction, or receive no intervention. The restricted-accessgroup attended the gym 51 percent more than the no-intervention group over the study period. A follow-upstudy found that participants in bundling conditions were more likely to continue exercising after the study ended, suggesting bundle-reinforced habits had formed. The research provided direct experimental evidence that temptation bundling translates present bias into a tool for promoting beneficial behaviour. |
Commitment Devices: Binding Future Choices
Commitment devices are advance arrangements that restrict your own future choices to prevent your present-biased future self from abandoning long-term goals when the temptation moment arrives. Research by Ariely and Wertenbroch found that people voluntarily chose binding deadlines when given the option, accepting self-imposed constraint in exchange for better performance outcomes. The voluntary choice of commitment reflects sophisticated awareness of one’s own present bias.
Ulysses contracts, named for Odysseus having himself tied to the mast to resist the Sirens, are the classic form: you arrange in advance to make the undesired behaviour costly or impossible when the temptation arrives. Financial commitment devices including gym payment structures, penalty-based savings accounts, and prepaid meal plan services all exploit the same mechanism: the committed cost of deviation makes the present self’s preference for immediate indulgence less compelling than the advance self’s preference for long-term benefit.
Thaler and Benartzi’s Save More Tomorrow programme demonstrated commitment devices at scale: workers who committed in advance to automatically increasing their savings rate with future pay rises achieved dramatically higher savings rates than control participants. The commitment moved the sacrifice into the future (always into the future, with each raise) rather than requiring immediate reduction in take-home pay, routing around present bias entirely rather than trying to overcome it.
| EXPERIENCE NOTE |
| Behavioural coaches and personal trainers consistently report the same pattern across clients: the most successful long-term behaviour change consistently involves some form of advance commitment structure rather than relying on in-the-moment motivation. Clients who prepay for sessions, book multiple sessions in advance, or create social accountability commitments with specific consequences show measurably better adherence than those relying on voluntary engagement. The commitment device does not replace motivation; it changes the decision architecture so that motivation is needed only once, at the point of commitment, rather than fresh at every instance. |
Designing Your Own Bundles and Commitments
Effective temptation bundles require identifying two things with genuine specificity: a beneficial activity you consistently avoid despite genuine intention, and an immediately rewarding activity you want to consume anyway. The pairing needs to feel fair rather than punitive: restricting your favourite podcast to gym sessions works better than restricting a basic life pleasure. The better the reward, the more powerful the bundle.
Effective commitment devices require identifying the specific point at which your present self is most likely to defect from the advance self’s intention, and placing a cost or barrier at exactly that point. The commitment needs to be set up in a cool, forward-looking cognitive state rather than during a moment of temptation. Research on commitment timing found that commitments made during planning mode are more effective than those made during the motivational moment because present bias is less active during cool planning.
Digital commitment tools have made both strategies more accessible: podcast apps that require location check-in before unlocking episodes, website blockers that require inconvenient override procedures during work hours, and savings apps that make funds inaccessible for defined periods. Research on these digital commitment tools finds consistent positive effects on targeted behaviours, with effect sizes larger than equivalent willpower-based approaches.
| KEY TAKEAWAY |
| Temptation bundling and commitment devices both change the objective choice environment in advance rather than fighting temptation at the moment. Temptation bundling pairs immediate reward with beneficial behaviour and restricts the reward to that context. Commitment devices make deviation from the advance plan costly. Both exploit the insight that the planning self and the temptation-moment self are psychologically different agents with different preferences, and that designing for the temptation moment in advance is more reliable than hoping the planning self’s preferences survive into it. |
Frequently Asked Questions
How do I design my own temptation bundle?
Identify an activity you consistently avoid (exercise, administrative tasks) and an immediately rewarding activity you already want to consume (a favourite podcast or series). Restrict access to the rewarding activity exclusively to the bundled context. The restriction must be genuine: freely available rewards lose their bundling power. Start with one bundle and one activity pair before adding more.
What makes a commitment device effective?
Research identifies: set it up during a calm planning state rather than a moment of temptation; make the penalty meaningful but not catastrophic; make the mechanism automatic rather than requiring ongoing active maintenance; and add a social or accountability dimension where possible. Public commitments to others are more binding than private ones in most research.
Can I use both strategies together?
Yes, and the combination is often more effective than either alone. Committing to attend the gym (commitment device) while restricting access to a favourite podcast to gym sessions (temptation bundle) addresses both the attendance decision and the experience of attending. The two strategies address different aspects of the self-control problem.
Are commitment devices manipulative if someone else sets them up?
Research on paternalistic commitment devices distinguishes between those that restrict choice entirely and nudges that preserve free choice while changing its architecture. Commitment devices that preserve exit options while making exit costly preserve autonomy. The ethical distinction centres on whether the commitment reflects the individual’s own advance preferences or someone else’s preferences imposed on them.
Why do commitment devices fail sometimes?
Research on commitment device failure identifies: the penalty is not meaningful enough to deter the temptation; the commitment device requires active maintenance that the present-biased self neglects; the device is set up during a motivated state and the motivation does not transfer; or the advance self’s stated preferences do not accurately reflect their genuine preferences, making the commitment feel imposed rather than self-authored.
