 Incentives are central to economics and are used across the public and private sectors to influence behaviour. Psychological phenomena from behavioural economics allow us to design incentive-based interventions that are more effective at delivering improved outcomes. Personal incentives have been used to motivate patients and general populations to change their behaviour. Examples of behaviours targeted include smoking and drug use cessation. Incentives can include cash, vouchers or benefits-in-kind and they can have a profound effect on individual behaviour at a relatively small cost. Interest in offering incentives to foster healthier lifestyles has increased, as the full economic and social costs of bad choices and unhealthy behaviour have become apparent. Incentives have previously been used to improve cancer screening rates, but they have been targeted at the providers of the service rather than people invited to attend for screening. Financial incentives have been seen to be more effective in increasing performance of infrequent behaviours e.g. vaccinations rather than in more sustained behaviours e.g. smoking. As screening usually requires discrete one-off behaviours, incentives may be particularly effective in increasing their uptake. 